Bug 834732 - Audit callers of GetNativeContext and use AutoPushJSContext where appropriate. r=mrbkap

caps/src/nsSecurityManagerFactory.cpp

@@ -26,6 +26,7 @@
 #include "nsIDocument.h"
 #include "jsfriendapi.h"
 #include "xpcprivate.h"
+#include "nsContentUtils.h"
 #include "mozilla/Preferences.h"
 #include "mozilla/Telemetry.h"
 
@@ -64,7 +65,7 @@ static JSFunctionSpec PrivilegeManager_static_methods[] = {
 NS_IMETHODIMP 
 nsSecurityNameSet::InitializeNameSet(nsIScriptContext* aScriptContext)
 {
-    JSContext* cx = aScriptContext->GetNativeContext();
+    AutoPushJSContext cx(aScriptContext->GetNativeContext());
     JSObject *global = JS_ObjectToInnerObject(cx, JS_GetGlobalObject(cx));
 
     /*

content/base/src/EventSource.cpp

@@ -1227,7 +1227,7 @@ EventSource::DispatchAllMessageEvents()
   nsIScriptContext* scriptContext = sgo->GetContext();
   NS_ENSURE_TRUE_VOID(scriptContext);
 
-  JSContext* cx = scriptContext->GetNativeContext();
+  AutoPushJSContext cx(scriptContext->GetNativeContext());
   NS_ENSURE_TRUE_VOID(cx);
 
   while (mMessagesToDispatch.GetSize() > 0) {

content/base/src/WebSocket.cpp

@@ -881,7 +881,7 @@ WebSocket::CreateAndDispatchMessageEvent(const nsACString& aData,
   nsIScriptContext* scriptContext = sgo->GetContext();
   NS_ENSURE_TRUE(scriptContext, NS_ERROR_FAILURE);
 
-  JSContext* cx = scriptContext->GetNativeContext();
+  AutoPushJSContext cx(scriptContext->GetNativeContext());
   NS_ENSURE_TRUE(cx, NS_ERROR_FAILURE);
 
   // Create appropriate JS object for message

content/base/src/nsContentUtils.cpp

@@ -6412,8 +6412,8 @@ nsContentUtils::IsPatternMatching(nsAString& aValue, nsAString& aPattern,
   NS_ASSERTION(aDocument, "aDocument should be a valid pointer (not null)");
   NS_ENSURE_TRUE(aDocument->GetScriptGlobalObject(), true);
 
-  JSContext* cx = aDocument->GetScriptGlobalObject()->
-                                  GetContext()->GetNativeContext();
+  AutoPushJSContext cx(aDocument->GetScriptGlobalObject()->
+                       GetContext()->GetNativeContext());
   NS_ENSURE_TRUE(cx, true);
 
   JSAutoRequest ar(cx);

content/base/src/nsDOMDataChannel.cpp

@@ -45,6 +45,8 @@ extern PRLogModuleInfo* GetDataChannelLog();
 #undef GetBinaryType
 #endif
 
+using namespace mozilla;
+
 class nsDOMDataChannel : public nsDOMEventTargetHelper,
                          public nsIDOMDataChannel,
                          public mozilla::DataChannelListener
@@ -393,7 +395,7 @@ nsDOMDataChannel::DoOnMessageAvailable(const nsACString& aData,
   nsIScriptContext* sc = sgo->GetContext();
   NS_ENSURE_TRUE(sc, NS_ERROR_FAILURE);
 
-  JSContext* cx = sc->GetNativeContext();
+  AutoPushJSContext cx(sc->GetNativeContext());
   NS_ENSURE_TRUE(cx, NS_ERROR_FAILURE);
 
   JSAutoRequest ar(cx);

content/base/src/nsDocument.cpp

@@ -3983,19 +3983,8 @@ nsDocument::SetScriptGlobalObject(nsIScriptGlobalObject *aScriptGlobalObject)
       JSObject *obj = GetWrapperPreserveColor();
       if (obj) {
         JSObject *newScope = aScriptGlobalObject->GetGlobalJSObject();
-        nsIScriptContext *scx = aScriptGlobalObject->GetContext();
-        JSContext *cx = scx ? scx->GetNativeContext() : nullptr;
-        if (!cx) {
-          nsContentUtils::ThreadJSContextStack()->Peek(&cx);
-          if (!cx) {
-            cx = nsContentUtils::ThreadJSContextStack()->GetSafeJSContext();
-            NS_ASSERTION(cx, "Uhoh, no context, this is bad!");
-          }
-        }
-        if (cx) {
-          NS_ASSERTION(JS_GetGlobalForObject(cx, obj) == newScope,
-                       "Wrong scope, this is really bad!");
-        }
+        NS_ASSERTION(js::GetGlobalForObjectCrossCompartment(obj) == newScope,
+                     "Wrong scope, this is really bad!");
       }
     }
 #endif
@@ -6829,7 +6818,7 @@ nsDocument::IsScriptEnabled()
   nsIScriptContext *scriptContext = globalObject->GetContext();
   NS_ENSURE_TRUE(scriptContext, false);
 
-  JSContext* cx = scriptContext->GetNativeContext();
+  AutoPushJSContext cx(scriptContext->GetNativeContext());
   NS_ENSURE_TRUE(cx, false);
 
   bool enabled;
@@ -8547,7 +8536,7 @@ nsDocument::GetStateObject(nsIVariant** aState)
 
   nsCOMPtr<nsIVariant> stateObj;
   if (!mStateObjectCached && mStateObjectContainer) {
-    JSContext *cx = nsContentUtils::GetContextFromDocument(this);
+    AutoPushJSContext cx(nsContentUtils::GetContextFromDocument(this));
     mStateObjectContainer->
       DeserializeToVariant(cx, getter_AddRefs(mStateObjectCached));
   }

content/base/src/nsFrameLoader.cpp

@@ -2363,7 +2363,7 @@ nsFrameLoader::EnsureMessageManager()
   nsIScriptContext* sctx = mOwnerContent->GetContextForEventHandlers(&rv);
   NS_ENSURE_SUCCESS(rv, rv);
   NS_ENSURE_STATE(sctx);
-  JSContext* cx = sctx->GetNativeContext();
+  AutoPushJSContext cx(sctx->GetNativeContext());
   NS_ENSURE_STATE(cx);
 
   nsCOMPtr<nsIDOMChromeWindow> chromeWindow =

content/base/src/nsScriptLoader.cpp

@@ -822,6 +822,7 @@ nsScriptLoader::EvaluateScript(nsScriptLoadRequest* aRequest,
   if (!context) {
     return NS_ERROR_FAILURE;
   }
+  AutoPushJSContext cx(context->GetNativeContext());
 
   bool oldProcessingScriptTag = context->GetProcessingScriptTag();
   context->SetProcessingScriptTag(true);
@@ -837,7 +838,7 @@ nsScriptLoader::EvaluateScript(nsScriptLoadRequest* aRequest,
 
   JSVersion version = JSVersion(aRequest->mJSVersion);
   if (version != JSVERSION_UNKNOWN) {
-    JS::CompileOptions options(context->GetNativeContext());
+    JS::CompileOptions options(cx);
     options.setFileAndLine(url.get(), aRequest->mLineNo)
            .setVersion(JSVersion(aRequest->mJSVersion));
     if (aRequest->mOriginPrincipal) {
@@ -850,8 +851,6 @@ nsScriptLoader::EvaluateScript(nsScriptLoadRequest* aRequest,
   // Put the old script back in case it wants to do anything else.
   mCurrentScript = oldCurrent;
 
-  JSContext *cx = nullptr; // Initialize this to keep GCC happy.
-  cx = context->GetNativeContext();
   JSAutoRequest ar(cx);
   context->SetProcessingScriptTag(oldProcessingScriptTag);
   return rv;

content/html/document/src/nsHTMLContentSink.cpp

@@ -1341,8 +1341,7 @@ IsScriptEnabled(nsIDocument *aDoc, nsIDocShell *aContainer)
 
   nsIScriptContext *scriptContext = globalObject->GetContext();
   NS_ENSURE_TRUE(scriptContext, true);
-
-  JSContext* cx = scriptContext->GetNativeContext();
+  JSContext *cx = scriptContext->GetNativeContext();
   NS_ENSURE_TRUE(cx, true);
 
   bool enabled = true;

content/media/webaudio/MediaBufferDecoder.cpp

@@ -663,7 +663,7 @@ WebAudioDecodeJob::FinalizeBufferData()
   MOZ_ASSERT(mOutput);
   MOZ_ASSERT(mChannels == mChannelBuffers.Length());
 
-  JSContext* cx = GetJSContext();
+  AutoPushJSContext cx(GetJSContext());
   if (!cx) {
     return false;
   }
@@ -696,7 +696,7 @@ WebAudioDecodeJob::AllocateBuffer()
   MOZ_ASSERT(NS_IsMainThread());
 
   // First, get a JSContext
-  JSContext* cx = GetJSContext();
+  AutoPushJSContext cx(GetJSContext());
   if (!cx) {
     return false;
   }

content/xbl/src/nsBindingManager.cpp

@@ -45,6 +45,8 @@
 #include "nsThreadUtils.h"
 #include "mozilla/dom/NodeListBinding.h"
 
+using namespace mozilla;
+
 // ==================================================================
 // = nsAnonymousContentList 
 // ==================================================================
@@ -1177,7 +1179,7 @@ nsBindingManager::GetBindingImplementation(nsIContent* aContent, REFNSIID aIID,
       if (!context)
         return NS_NOINTERFACE;
 
-      JSContext* jscontext = context->GetNativeContext();
+      AutoPushJSContext jscontext(context->GetNativeContext());
       if (!jscontext)
         return NS_NOINTERFACE;
 

content/xbl/src/nsXBLBinding.cpp

@@ -1263,7 +1263,7 @@ nsXBLBinding::AllowScripts()
     return false;
   }
   
-  JSContext* cx = context->GetNativeContext();
+  AutoPushJSContext cx(context->GetNativeContext());
 
   nsCOMPtr<nsIDocument> ourDocument =
     mPrototypeBinding->XBLDocumentInfo()->GetDocument();

content/xbl/src/nsXBLDocumentInfo.cpp

@@ -272,7 +272,7 @@ nsXBLDocGlobalObject::EnsureScriptEnvironment()
 
   mScriptContext = newCtx;
 
-  JSContext *cx = mScriptContext->GetNativeContext();
+  AutoPushJSContext cx(mScriptContext->GetNativeContext());
   JSAutoRequest ar(cx);
 
   // nsJSEnvironment set the error reporter to NS_ScriptErrorReporter so

content/xbl/src/nsXBLProtoImpl.cpp

@@ -86,7 +86,7 @@ nsXBLProtoImpl::InstallImplementation(nsXBLPrototypeBinding* aPrototypeBinding,
   JSObject * targetScriptObject;
   holder->GetJSObject(&targetScriptObject);
 
-  JSContext *cx = context->GetNativeContext();
+  AutoPushJSContext cx(context->GetNativeContext());
   JSAutoRequest ar(cx);
   JSAutoCompartment ac(cx, targetClassObject);
   AutoVersionChecker avc(cx);
@@ -172,7 +172,7 @@ nsXBLProtoImpl::InitTargetObjects(nsXBLPrototypeBinding* aBinding,
 
   // Because our prototype implementation has a class, we need to build up a corresponding
   // class for the concrete implementation in the bound document.
-  JSContext* jscontext = aContext->GetNativeContext();
+  AutoPushJSContext jscontext(aContext->GetNativeContext());
   JSObject* global = sgo->GetGlobalJSObject();
   nsCOMPtr<nsIXPConnectJSObjectHolder> wrapper;
   jsval v;
@@ -211,7 +211,7 @@ nsXBLProtoImpl::CompilePrototypeMembers(nsXBLPrototypeBinding* aBinding)
   nsIScriptContext *context = globalObject->GetContext();
   NS_ENSURE_TRUE(context, NS_ERROR_OUT_OF_MEMORY);
 
-  JSContext *cx = context->GetNativeContext();
+  AutoPushJSContext cx(context->GetNativeContext());
   JSObject *global = globalObject->GetGlobalJSObject();
   
 
@@ -348,7 +348,7 @@ nsXBLProtoImpl::Read(nsIScriptContext* aContext,
                      nsIScriptGlobalObject* aGlobal)
 {
   // Set up a class object first so that deserialization is possible
-  JSContext *cx = aContext->GetNativeContext();
+  AutoPushJSContext cx(aContext->GetNativeContext());
   JSObject *global = aGlobal->GetGlobalJSObject();
 
   JSObject* classObject;

content/xbl/src/nsXBLProtoImplField.cpp

@@ -400,7 +400,7 @@ nsXBLProtoImplField::InstallField(nsIScriptContext* aContext,
   nsAutoCString uriSpec;
   aBindingDocURI->GetSpec(uriSpec);
   
-  JSContext* cx = aContext->GetNativeContext();
+  AutoPushJSContext cx(aContext->GetNativeContext());
   NS_ASSERTION(!::JS_IsExceptionPending(cx),
                "Shouldn't get here when an exception is pending!");
   

content/xbl/src/nsXBLProtoImplMethod.cpp

@@ -20,6 +20,8 @@
 #include "xpcpublic.h"
 #include "nsXBLPrototypeBinding.h"
 
+using namespace mozilla;
+
 nsXBLProtoImplMethod::nsXBLProtoImplMethod(const PRUnichar* aName) :
   nsXBLProtoImplMember(aName), 
   mUncompiledMethod(BIT_UNCOMPILED)
@@ -192,7 +194,7 @@ nsXBLProtoImplMethod::CompileMember(nsIScriptContext* aContext, const nsCString&
   }
 
   JSObject* methodObject = nullptr;
-  JSContext* cx = aContext->GetNativeContext();
+  AutoPushJSContext cx(aContext->GetNativeContext());
   JSAutoRequest ar(cx);
   JSAutoCompartment ac(cx, aClassObject);
   JS::CompileOptions options(cx);
@@ -287,7 +289,7 @@ nsXBLProtoImplAnonymousMethod::Execute(nsIContent* aBoundElement)
 
   nsAutoMicroTask mt;
 
-  JSContext* cx = context->GetNativeContext();
+  AutoPushJSContext cx(context->GetNativeContext());
 
   JSObject* globalObject = global->GetGlobalJSObject();
 

content/xbl/src/nsXBLProtoImplProperty.cpp

@@ -9,6 +9,7 @@
 #include "nsIContent.h"
 #include "nsXBLProtoImplProperty.h"
 #include "nsUnicharUtils.h"
+#include "nsContentUtils.h"
 #include "nsReadableUtils.h"
 #include "nsIScriptContext.h"
 #include "nsJSUtils.h"
@@ -17,6 +18,8 @@
 #include "nsXBLSerialize.h"
 #include "xpcpublic.h"
 
+using namespace mozilla;
+
 nsXBLProtoImplProperty::nsXBLProtoImplProperty(const PRUnichar* aName,
                                                const PRUnichar* aGetter, 
                                                const PRUnichar* aSetter,
@@ -207,7 +210,7 @@ nsXBLProtoImplProperty::CompileMember(nsIScriptContext* aContext, const nsCStrin
     if (!getter.IsEmpty()) {
       // Compile into a temp object so we don't wipe out mGetterText
       JSObject* getterObject = nullptr;
-      JSContext* cx = aContext->GetNativeContext();
+      AutoPushJSContext cx(aContext->GetNativeContext());
       JSAutoRequest ar(cx);
       JSAutoCompartment ac(cx, aClassObject);
       JS::CompileOptions options(cx);
@@ -257,7 +260,7 @@ nsXBLProtoImplProperty::CompileMember(nsIScriptContext* aContext, const nsCStrin
     if (!setter.IsEmpty()) {
       // Compile into a temp object so we don't wipe out mSetterText
       JSObject* setterObject = nullptr;
-      JSContext* cx = aContext->GetNativeContext();
+      AutoPushJSContext cx(aContext->GetNativeContext());
       JSAutoRequest ar(cx);
       JSAutoCompartment ac(cx, aClassObject);
       JS::CompileOptions options(cx);

content/xbl/src/nsXBLPrototypeHandler.cpp

@@ -290,7 +290,7 @@ nsXBLPrototypeHandler::ExecuteHandler(nsIDOMEventTarget* aTarget,
   rv = EnsureEventHandler(boundGlobal, boundContext, onEventAtom, handler);
   NS_ENSURE_SUCCESS(rv, rv);
 
-  JSContext* cx = boundContext->GetNativeContext();
+  AutoPushJSContext cx(boundContext->GetNativeContext());
   JSAutoRequest ar(cx);
   JSObject* globalObject = boundGlobal->GetGlobalJSObject();
   JSObject* scopeObject = xpc::GetXBLScope(cx, globalObject);
@@ -370,7 +370,7 @@ nsXBLPrototypeHandler::EnsureEventHandler(nsIScriptGlobalObject* aGlobal,
   nsDependentString handlerText(mHandlerText);
   NS_ENSURE_TRUE(!handlerText.IsEmpty(), NS_ERROR_FAILURE);
 
-  JSContext* cx = aBoundContext->GetNativeContext();
+  AutoPushJSContext cx(aBoundContext->GetNativeContext());
   JSObject* globalObject = aGlobal->GetGlobalJSObject();
   JSObject* scopeObject = xpc::GetXBLScope(cx, globalObject);
 

content/xbl/src/nsXBLSerialize.cpp

@@ -8,12 +8,14 @@
 #include "nsContentUtils.h"
 #include "jsdbgapi.h"
 
+using namespace mozilla;
+
 nsresult
 XBL_SerializeFunction(nsIScriptContext* aContext,
                       nsIObjectOutputStream* aStream,
                       JSObject* aFunctionObject)
 {
-  JSContext* cx = aContext->GetNativeContext();
+  AutoPushJSContext cx(aContext->GetNativeContext());
   return nsContentUtils::XPConnect()->WriteFunction(aStream, cx, aFunctionObject);
 }
 
@@ -22,7 +24,7 @@ XBL_DeserializeFunction(nsIScriptContext* aContext,
                         nsIObjectInputStream* aStream,
                         JSObject** aFunctionObjectp)
 {
-  JSContext* cx = aContext->GetNativeContext();
+  AutoPushJSContext cx(aContext->GetNativeContext());
   nsresult rv = nsContentUtils::XPConnect()->ReadFunction(aStream, cx, aFunctionObjectp);
   NS_ENSURE_SUCCESS(rv, rv);
 

content/xul/document/src/nsXULPrototypeDocument.cpp

@@ -33,6 +33,7 @@
 #include "mozilla/dom/BindingUtils.h"
 
 using mozilla::dom::DestroyProtoAndIfaceCache;
+using mozilla::AutoPushJSContext;
 
 static NS_DEFINE_CID(kDOMScriptObjectFactoryCID,
                      NS_DOM_SCRIPT_OBJECT_FACTORY_CID);
@@ -757,7 +758,7 @@ nsXULPDGlobalObject::EnsureScriptEnvironment()
   // attach it as the global for this context.  Then, we
   // will re-fetch the global and set it up in our language globals array.
   {
-    JSContext *cx = ctxNew->GetNativeContext();
+    AutoPushJSContext cx(ctxNew->GetNativeContext());
     JSAutoRequest ar(cx);
 
     JSObject *newGlob = JS_NewGlobalObject(cx, &gSharedGlobalClass,

content/xul/templates/src/nsXULTemplateBuilder.cpp

@@ -71,6 +71,7 @@
 #include "nsContentUtils.h"
 
 using namespace mozilla::dom;
+using namespace mozilla;
 
 //----------------------------------------------------------------------
 
@@ -1387,7 +1388,7 @@ nsXULTemplateBuilder::InitHTMLTemplateRoot()
     if (! context)
         return NS_ERROR_UNEXPECTED;
 
-    JSContext* jscontext = context->GetNativeContext();
+    AutoPushJSContext jscontext(context->GetNativeContext());
     NS_ASSERTION(context != nullptr, "no jscontext");
     if (! jscontext)
         return NS_ERROR_UNEXPECTED;

dom/base/DOMRequest.cpp

@@ -18,6 +18,7 @@
 using mozilla::dom::DOMRequest;
 using mozilla::dom::DOMRequestService;
 using mozilla::dom::DOMCursor;
+using mozilla::AutoPushJSContext;
 
 DOMRequest::DOMRequest(nsIDOMWindow* aWindow)
   : mResult(JSVAL_VOID)
@@ -240,9 +241,10 @@ public:
     NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
     nsresult rv;
     nsIScriptContext* sc = mReq->GetContextForEventHandlers(&rv);
-    MOZ_ASSERT(NS_SUCCEEDED(rv) && sc->GetNativeContext());
-    JSAutoRequest ar(sc->GetNativeContext());
-    JS_AddValueRoot(sc->GetNativeContext(), &mResult);
+    AutoPushJSContext cx(sc->GetNativeContext());
+    MOZ_ASSERT(NS_SUCCEEDED(rv) && cx);
+    JSAutoRequest ar(cx);
+    JS_AddValueRoot(cx, &mResult);
   }
 
   NS_IMETHODIMP
@@ -257,12 +259,13 @@ public:
     NS_ASSERTION(NS_IsMainThread(), "Wrong thread!");
     nsresult rv;
     nsIScriptContext* sc = mReq->GetContextForEventHandlers(&rv);
-    MOZ_ASSERT(NS_SUCCEEDED(rv) && sc->GetNativeContext());
+    AutoPushJSContext cx(sc->GetNativeContext());
+    MOZ_ASSERT(NS_SUCCEEDED(rv) && cx);
 
     // We need to build a new request, otherwise we assert since there won't be
     // a request available yet.
-    JSAutoRequest ar(sc->GetNativeContext());
-    JS_RemoveValueRoot(sc->GetNativeContext(), &mResult);
+    JSAutoRequest ar(cx);
+    JS_RemoveValueRoot(cx, &mResult);
   }
 private:
   nsRefPtr<DOMRequest> mReq;

dom/base/nsGlobalWindow.cpp

@@ -1339,7 +1339,7 @@ nsGlobalWindow::FreeInnerObjects()
 
   // Kill all of the workers for this window.
   nsIScriptContext *scx = GetContextInternal();
-  JSContext *cx = scx ? scx->GetNativeContext() : nullptr;
+  AutoPushJSContext cx(scx ? scx->GetNativeContext() : nullptr);
   mozilla::dom::workers::CancelWorkersForWindow(cx, this);
 
   // Close all IndexedDB databases for this window.
@@ -1893,7 +1893,7 @@ NS_IMPL_ISUPPORTS1(WindowStateHolder, WindowStateHolder)
 nsresult
 nsGlobalWindow::CreateOuterObject(nsGlobalWindow* aNewInner)
 {
-  JSContext* cx = mContext->GetNativeContext();
+  AutoPushJSContext cx(mContext->GetNativeContext());
 
   JSObject* outer = NewOuterWindowProxy(cx, aNewInner->FastGetGlobalJSObject(),
                                         IsChromeWindow());
@@ -2995,11 +2995,10 @@ nsGlobalWindow::SetArguments(nsIArray *aArguments, nsIPrincipal *aOrigin)
 nsresult
 nsGlobalWindow::DefineArgumentsProperty(nsIArray *aArguments)
 {
-  JSContext *cx;
   nsIScriptContext *ctx = GetOuterWindowInternal()->mContext;
-  NS_ENSURE_TRUE(aArguments && ctx &&
-                 (cx = ctx->GetNativeContext()),
-                 NS_ERROR_NOT_INITIALIZED);
+  NS_ENSURE_TRUE(aArguments && ctx, NS_ERROR_NOT_INITIALIZED);
+  AutoPushJSContext cx(ctx->GetNativeContext());
+  NS_ENSURE_TRUE(cx, NS_ERROR_NOT_INITIALIZED);
 
   if (mIsModalContentWindow) {
     // Modal content windows don't have an "arguments" property, they
@@ -6486,25 +6485,10 @@ PostMessageEvent::Run()
                     "should have been passed an outer window!");
 
   // Get the JSContext for the target window
-  JSContext* cx = nullptr;
   nsIScriptContext* scriptContext = mTargetWindow->GetContext();
-  if (scriptContext) {
-    cx = scriptContext->GetNativeContext();
-  }
-
-  if (!cx) {
-    // This can happen if mTargetWindow has been closed.  To avoid leaking,
-    // we need to find a JSContext.
-    nsIThreadJSContextStack* cxStack = nsContentUtils::ThreadJSContextStack();
-    if (cxStack) {
-      cx = cxStack->GetSafeJSContext();
-    }
-
-    if (!cx) {
-      NS_WARNING("Cannot find a JSContext!  Leaking PostMessage buffer.");
-      return NS_ERROR_FAILURE;
-    }
-  }
+  AutoPushJSContext cx(scriptContext ? scriptContext->GetNativeContext()
+                                     : nsContentUtils::GetSafeJSContext());
+  MOZ_ASSERT(cx);
 
   // If we bailed before this point we're going to leak mMessage, but
   // that's probably better than crashing.
@@ -9960,7 +9944,8 @@ nsGlobalWindow::RunTimeoutHandler(nsTimeout* aTimeout,
     uint32_t lineNo = 0;
     handler->GetLocation(&filename, &lineNo);
 
-    JS::CompileOptions options(aScx->GetNativeContext());
+    AutoPushJSContext cx(aScx->GetNativeContext());
+    JS::CompileOptions options(cx);
     options.setFileAndLine(filename, lineNo)
            .setVersion(JSVERSION_DEFAULT);
     aScx->EvaluateString(nsDependentString(script), *FastGetGlobalJSObject(),
@@ -10753,7 +10738,7 @@ nsGlobalWindow::SuspendTimeouts(uint32_t aIncrease,
 
     // Suspend all of the workers for this window.
     nsIScriptContext *scx = GetContextInternal();
-    JSContext *cx = scx ? scx->GetNativeContext() : nullptr;
+    AutoPushJSContext cx(scx ? scx->GetNativeContext() : nullptr);
     mozilla::dom::workers::SuspendWorkersForWindow(cx, this);
 
     TimeStamp now = TimeStamp::Now();
@@ -10833,7 +10818,7 @@ nsGlobalWindow::ResumeTimeouts(bool aThawChildren)
 
     // Resume all of the workers for this window.
     nsIScriptContext *scx = GetContextInternal();
-    JSContext *cx = scx ? scx->GetNativeContext() : nullptr;
+    AutoPushJSContext cx(scx ? scx->GetNativeContext() : nullptr);
     mozilla::dom::workers::ResumeWorkersForWindow(cx, this);
 
     // Restore all of the timeouts, using the stored time remaining
@@ -11335,7 +11320,7 @@ nsGlobalChromeWindow::GetMessageManager(nsIMessageBroadcaster** aManager)
   if (!mMessageManager) {
     nsIScriptContext* scx = GetContextInternal();
     NS_ENSURE_STATE(scx);
-    JSContext* cx = scx->GetNativeContext();
+    AutoPushJSContext cx(scx->GetNativeContext());
     NS_ENSURE_STATE(cx);
     nsCOMPtr<nsIMessageBroadcaster> globalMM =
       do_GetService("@mozilla.org/globalmessagemanager;1");

dom/devicestorage/nsDeviceStorage.cpp

@@ -801,7 +801,7 @@ jsval InterfaceToJsval(nsPIDOMWindow* aWindow, nsISupports* aObject, const nsIID
     return JSVAL_NULL;
   }
 
-  JSContext *cx = scriptContext->GetNativeContext();
+  AutoPushJSContext cx(scriptContext->GetNativeContext());
   if (!cx) {
     return JSVAL_NULL;
   }
@@ -853,7 +853,7 @@ jsval StringToJsval(nsPIDOMWindow* aWindow, nsAString& aString)
     return JSVAL_NULL;
   }
 
-  JSContext *cx = scriptContext->GetNativeContext();
+  AutoPushJSContext cx(scriptContext->GetNativeContext());
   if (!cx) {
     return JSVAL_NULL;
   }

dom/file/ArchiveRequest.cpp

@@ -129,7 +129,7 @@ ArchiveRequest::ReaderReady(nsTArray<nsCOMPtr<nsIDOMFile> >& aFileList,
   nsIScriptContext* sc = GetContextForEventHandlers(&rv);
   NS_ENSURE_STATE(sc);
 
-  JSContext* cx = sc->GetNativeContext();
+  AutoPushJSContext cx(sc->GetNativeContext());
   NS_ASSERTION(cx, "Failed to get a context!");
 
   JSObject* global = sc->GetNativeGlobal();

dom/file/FileRequest.cpp

@@ -73,7 +73,7 @@ FileRequest::NotifyHelperCompleted(FileHelper* aFileHelper)
   nsIScriptContext* sc = GetContextForEventHandlers(&rv);
   NS_ENSURE_STATE(sc);
 
-  JSContext* cx = sc->GetNativeContext();
+  AutoPushJSContext cx(sc->GetNativeContext());
   NS_ASSERTION(cx, "Failed to get a context!");
 
   JSObject* global = sc->GetNativeGlobal();

dom/indexedDB/IDBRequest.cpp

@@ -96,7 +96,7 @@ IDBRequest::NotifyHelperCompleted(HelperBase* aHelper)
   }
 
   // Otherwise we need to get the result from the helper.
-  JSContext* cx = GetJSContext();
+  AutoPushJSContext cx(GetJSContext());
   if (!cx) {
     NS_WARNING("Failed to get safe JSContext!");
     rv = NS_ERROR_DOM_INDEXEDDB_UNKNOWN_ERR;

dom/network/src/MobileConnection.cpp

@@ -212,7 +212,7 @@ MobileConnection::Observe(nsISupports* aSubject,
     nsresult rv;
     nsIScriptContext* sc = GetContextForEventHandlers(&rv);
     NS_ENSURE_STATE(sc);
-    JSContext* cx = sc->GetNativeContext();
+    AutoPushJSContext cx(sc->GetNativeContext());
     NS_ASSERTION(cx, "Failed to get a context!");
 
     nsCOMPtr<nsIJSON> json(new nsJSON());

dom/plugins/base/nsNPAPIPlugin.cpp

@@ -1221,7 +1221,7 @@ _getwindowobject(NPP npp)
     NPN_PLUGIN_LOG(PLUGIN_LOG_ALWAYS,("NPN_getwindowobject called from the wrong thread\n"));
     return nullptr;
   }
-  JSContext *cx = GetJSContextFromNPP(npp);
+  AutoPushJSContext cx(GetJSContextFromNPP(npp));
   NS_ENSURE_TRUE(cx, nullptr);
 
   // Using ::JS_GetGlobalObject(cx) is ok here since the window we
@@ -1248,7 +1248,7 @@ _getpluginelement(NPP npp)
   if (!element)
     return nullptr;
 
-  JSContext *cx = GetJSContextFromNPP(npp);
+  AutoPushJSContext cx(GetJSContextFromNPP(npp));
   NS_ENSURE_TRUE(cx, nullptr);
 
   nsCOMPtr<nsIXPConnect> xpc(do_GetService(nsIXPConnect::GetCID()));
@@ -1519,7 +1519,7 @@ _evaluate(NPP npp, NPObject* npobj, NPString *script, NPVariant *result)
   nsIDocument *doc = GetDocumentFromNPP(npp);
   NS_ENSURE_TRUE(doc, false);
 
-  JSContext *cx = GetJSContextFromDoc(doc);
+  AutoPushJSContext cx(GetJSContextFromDoc(doc));
   NS_ENSURE_TRUE(cx, false);
 
   nsCOMPtr<nsIScriptContext> scx = GetScriptContextFromJSContext(cx);

dom/sms/src/SmsManager.cpp

@@ -171,7 +171,7 @@ SmsManager::Send(const jsval& aNumber, const nsAString& aMessage, jsval* aReturn
   nsresult rv;
   nsIScriptContext* sc = GetContextForEventHandlers(&rv);
   NS_ENSURE_STATE(sc);
-  JSContext* cx = sc->GetNativeContext();
+  AutoPushJSContext cx(sc->GetNativeContext());
   NS_ASSERTION(cx, "Failed to get a context!");
 
   if (!aNumber.isString() &&
@@ -253,10 +253,10 @@ SmsManager::Delete(const jsval& aParam, nsIDOMMozSmsRequest** aRequest)
 
   nsresult rv;
   nsIScriptContext* sc = GetContextForEventHandlers(&rv);
+  AutoPushJSContext cx(sc->GetNativeContext());
   NS_ENSURE_STATE(sc);
   nsCOMPtr<nsIDOMMozSmsMessage> message =
-    do_QueryInterface(nsContentUtils::XPConnect()->GetNativeOfWrapper(
-          sc->GetNativeContext(), &aParam.toObject()));
+    do_QueryInterface(nsContentUtils::XPConnect()->GetNativeOfWrapper(cx, &aParam.toObject()));
   NS_ENSURE_TRUE(message, NS_ERROR_INVALID_ARG);
 
   int32_t id;

dom/sms/src/SmsRequest.cpp

@@ -190,7 +190,7 @@ SmsRequest::SetSuccessInternal(nsISupports* aObject)
     return false;
   }
 
-  JSContext* cx = sc->GetNativeContext();    
+  AutoPushJSContext cx(sc->GetNativeContext());
   NS_ASSERTION(cx, "Failed to get a context!");
 
   JSObject* global = sc->GetNativeGlobal();
@@ -514,7 +514,7 @@ SmsRequest::NotifyThreadList(const InfallibleTArray<ThreadListItem>& aItems)
   NS_ENSURE_SUCCESS_VOID(rv);
   NS_ENSURE_TRUE_VOID(sc);
 
-  JSContext* cx = sc->GetNativeContext();
+  AutoPushJSContext cx(sc->GetNativeContext());
   MOZ_ASSERT(cx);
 
   nsCOMPtr<nsIScriptGlobalObject> sgo = do_QueryInterface(GetOwner());

dom/src/jsurl/nsJSProtocolHandler.cpp

@@ -47,6 +47,8 @@
 #include "nsIContentSecurityPolicy.h"
 #include "nsSandboxFlags.h"
 
+using mozilla::AutoPushJSContext;
+
 static NS_DEFINE_CID(kJSURICID, NS_JSURI_CID);
 
 class nsJSThunk : public nsIInputStream
@@ -239,13 +241,7 @@ nsresult nsJSThunk::EvaluateScript(nsIChannel *aChannel,
     if (!useSandbox) {
         //-- Don't outside a sandbox unless the script principal subsumes the
         //   principal of the context.
-        nsCOMPtr<nsIPrincipal> objectPrincipal;
-        rv = securityManager->
-            GetObjectPrincipal(scriptContext->GetNativeContext(),
-                               globalJSObject,
-                               getter_AddRefs(objectPrincipal));
-        if (NS_FAILED(rv))
-            return rv;
+        nsIPrincipal* objectPrincipal = nsContentUtils::GetObjectPrincipal(globalJSObject);
 
         bool subsumes;
         rv = principal->Subsumes(objectPrincipal, &subsumes);
@@ -258,7 +254,7 @@ nsresult nsJSThunk::EvaluateScript(nsIChannel *aChannel,
     JS::Value v = JS::UndefinedValue();
     // Finally, we have everything needed to evaluate the expression.
 
-    JSContext *cx = scriptContext->GetNativeContext();
+    AutoPushJSContext cx(scriptContext->GetNativeContext());
     JSAutoRequest ar(cx);
     if (useSandbox) {
         // We were asked to use a sandbox, or the channel owner isn't allowed

dom/telephony/Telephony.cpp

@@ -274,10 +274,10 @@ Telephony::GetActive(jsval* aActive)
   nsresult rv;
   nsIScriptContext* sc = GetContextForEventHandlers(&rv);
   NS_ENSURE_SUCCESS(rv, rv);
+  AutoPushJSContext cx(sc ? sc->GetNativeContext() : nullptr);
   if (sc) {
     rv =
-      nsContentUtils::WrapNative(sc->GetNativeContext(),
-                                 sc->GetNativeGlobal(),
+      nsContentUtils::WrapNative(cx, sc->GetNativeGlobal(),
                                  mActiveCall->ToISupports(), aActive);
     NS_ENSURE_SUCCESS(rv, rv);
   }
@@ -292,8 +292,9 @@ Telephony::GetCalls(jsval* aCalls)
     nsresult rv;
     nsIScriptContext* sc = GetContextForEventHandlers(&rv);
     NS_ENSURE_SUCCESS(rv, rv);
+    AutoPushJSContext cx(sc ? sc->GetNativeContext() : nullptr);
     if (sc) {
-      rv = nsTArrayToJSArray(sc->GetNativeContext(), mCalls, &calls);
+      rv = nsTArrayToJSArray(cx, mCalls, &calls);
       NS_ENSURE_SUCCESS(rv, rv);
 
       if (!mRooted) {

widget/cocoa/nsMenuX.mm

@@ -37,6 +37,7 @@
 #include "nsBindingManager.h"
 #include "nsIServiceManager.h"
 #include "nsXULPopupManager.h"
+#include "nsContentUtils.h"
 
 #include "jsapi.h"
 #include "nsIScriptGlobalObject.h"
@@ -47,6 +48,7 @@ static bool gConstructingMenu = false;
 static bool gMenuMethodsSwizzled = false;
 
 int32_t nsMenuX::sIndexingMenuLevel = 0;
+using mozilla::AutoPushJSContext;
 
 
 //
@@ -414,7 +416,7 @@ void nsMenuX::MenuConstruct()
         nsCOMPtr<nsIScriptContext> scriptContext = sgo->GetContext();
         JSObject* global = sgo->GetGlobalJSObject();
         if (scriptContext && global) {
-          JSContext* cx = (JSContext*)scriptContext->GetNativeContext();
+          AutoPushJSContext cx(scriptContext->GetNativeContext());
           if (cx) {
             nsCOMPtr<nsIXPConnectJSObjectHolder> wrapper;
             xpconnect->WrapNative(cx, global,

xpfe/components/directory/nsDirectoryViewer.cpp

@@ -51,6 +51,7 @@
 #include "nsXPCOMCID.h"
 #include "nsIDocument.h"
 #include "mozilla/Preferences.h"
+#include "nsContentUtils.h"
 
 using namespace mozilla;
 
@@ -157,7 +158,7 @@ nsHTTPIndex::OnFTPControlLog(bool server, const char *msg)
     nsIScriptContext *context = scriptGlobal->GetContext();
     NS_ENSURE_TRUE(context, NS_OK);
 
-    JSContext* cx = context->GetNativeContext();
+    AutoPushJSContext cx(context->GetNativeContext());
     NS_ENSURE_TRUE(cx, NS_OK);
 
     JSObject* global = JS_GetGlobalObject(cx);
@@ -235,7 +236,7 @@ nsHTTPIndex::OnStartRequest(nsIRequest *request, nsISupports* aContext)
     nsIScriptContext *context = scriptGlobal->GetContext();
     NS_ENSURE_TRUE(context, NS_ERROR_FAILURE);
 
-    JSContext* cx = context->GetNativeContext();
+    AutoPushJSContext cx(context->GetNativeContext());
     JSObject* global = JS_GetGlobalObject(cx);
 
     // Using XPConnect, wrap the HTTP index object...