Bug 852134 - simplify rooting and unrooting of SMS. r=smaug

dom/mobilemessage/src/SmsRequest.cpp

@@ -42,9 +42,7 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 
 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(SmsRequest,
                                                 nsDOMEventTargetHelper)
-  if (tmp->mResultRooted) {
-    tmp->UnrootResult();
-  }
+  tmp->mResult = JSVAL_VOID;
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mCursor)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mError)
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
@@ -90,7 +88,6 @@ SmsRequest::Create(SmsRequestParent* aRequestParent)
 
 SmsRequest::SmsRequest(SmsManager* aManager)
   : mResult(JSVAL_VOID)
-  , mResultRooted(false)
   , mDone(false)
   , mParentAlive(false)
   , mParent(nullptr)
@@ -100,7 +97,6 @@ SmsRequest::SmsRequest(SmsManager* aManager)
 
 SmsRequest::SmsRequest(MobileMessageManager* aManager)
   : mResult(JSVAL_VOID)
-  , mResultRooted(false)
   , mDone(false)
   , mParentAlive(false)
   , mParent(nullptr)
@@ -110,7 +106,6 @@ SmsRequest::SmsRequest(MobileMessageManager* aManager)
 
 SmsRequest::SmsRequest(SmsRequestParent* aRequestParent)
   : mResult(JSVAL_VOID)
-  , mResultRooted(false)
   , mDone(false)
   , mParentAlive(true)
   , mParent(aRequestParent)
@@ -120,9 +115,8 @@ SmsRequest::SmsRequest(SmsRequestParent* aRequestParent)
 
 SmsRequest::~SmsRequest()
 {
-  if (mResultRooted) {
-    UnrootResult();
-  }
+  mResult = JSVAL_VOID;
+  NS_DROP_JS_OBJECTS(this, SmsRequest);
 }
 
 void
@@ -132,31 +126,10 @@ SmsRequest::Reset()
   NS_ASSERTION(mResult != JSVAL_VOID, "mResult should be set if we try to reset!");
   NS_ASSERTION(!mError, "There should be no error if we try to reset!");
 
-  if (mResultRooted) {
-    UnrootResult();
-  }
-
   mResult = JSVAL_VOID;
   mDone = false;
 }
 
-void
-SmsRequest::RootResult()
-{
-  NS_ASSERTION(!mResultRooted, "Don't call RootResult() if already rooted!");
-  NS_HOLD_JS_OBJECTS(this, SmsRequest);
-  mResultRooted = true;
-}
-
-void
-SmsRequest::UnrootResult()
-{
-  NS_ASSERTION(mResultRooted, "Don't call UnrotResult() if not rooted!");
-  mResult = JSVAL_VOID;
-  NS_DROP_JS_OBJECTS(this, SmsRequest);
-  mResultRooted = false;
-}
-
 void
 SmsRequest::SetSuccess(nsIDOMMozSmsMessage* aMessage)
 {
@@ -218,10 +191,10 @@ SmsRequest::SetSuccessInternal(nsISupports* aObject)
   JSAutoRequest ar(cx);
   JSAutoCompartment ac(cx, global);
 
-  RootResult();
+  NS_HOLD_JS_OBJECTS(this, SmsRequest);
 
   if (NS_FAILED(nsContentUtils::WrapNative(cx, global, aObject, &mResult))) {
-    UnrootResult();
+    mResult = JSVAL_VOID;
     SetError(nsIMobileMessageCallback::INTERNAL_ERROR);
     return false;
   }

dom/mobilemessage/src/SmsRequest.h

@@ -91,16 +91,6 @@ private:
 
   nsresult SendMessageReply(const mobilemessage::MessageReply& aReply);
 
-  /**
-   * Root mResult (JS::Value) to prevent garbage collection.
-   */
-  void RootResult();
-
-  /**
-   * Unroot mResult (JS::Value) to allow garbage collection.
-   */
-  void UnrootResult();
-
   /**
    * Set the object in a success state with the result being aMessage.
    */
@@ -140,7 +130,6 @@ private:
   nsresult NotifyError(int32_t aError);
 
   JS::Value mResult;
-  bool      mResultRooted;
   bool      mDone;
   bool      mParentAlive;
   mobilemessage::SmsRequestParent* mParent;