Bug 1433309 - Annotate createMediaKeys promise reject with whether failure occurred due to pending shutdown. r=gerald

Around every Firefox update, Netflix see a spike in
MediaKeySystemAccess.createMediaKeys() promise rejects. I am wondering whether
this is caused by the browser restarting to apply a Firefox update while
Netflix's player is loading.  So add more detail to the promise reject as to
the state of the system, to try to validate that theory.

MozReview-Commit-ID: 4IDPsFwKCtq

--HG--
extra : rebase_source : 0a53acb623f895e598845c281edc73b926c74c28

dom/media/gmp/ChromiumCDMParent.cpp

@@ -12,6 +12,7 @@
 #include "GMPContentChild.h"
 #include "GMPContentParent.h"
 #include "GMPLog.h"
+#include "GMPService.h"
 #include "GMPUtils.h"
 #include "MediaPrefs.h"
 #include "mozilla/dom/MediaKeyMessageEventBinding.h"
@@ -44,17 +45,42 @@ bool
 ChromiumCDMParent::Init(ChromiumCDMCallback* aCDMCallback,
                         bool aAllowDistinctiveIdentifier,
                         bool aAllowPersistentState,
-                        nsIEventTarget* aMainThread)
+                        nsIEventTarget* aMainThread,
+                        nsCString& aOutFailureReason)
 {
-  GMP_LOG("ChromiumCDMParent::Init(this=%p)", this);
+  GMP_LOG("ChromiumCDMParent::Init(this=%p) shutdown=%d abormalShutdown=%d "
+          "actorDestroyed=%d",
+          this,
+          mIsShutdown,
+          mAbnormalShutdown,
+          mActorDestroyed);
   if (!aCDMCallback || !aMainThread) {
+    aOutFailureReason = nsPrintfCString("ChromiumCDMParent::Init() failed "
+                                        "nullCallback=%d nullMainThread=%d",
+                                        !aCDMCallback,
+                                        !aMainThread);
     GMP_LOG("ChromiumCDMParent::Init(this=%p) failure since aCDMCallback(%p) or"
             " aMainThread(%p) is nullptr", this, aCDMCallback, aMainThread);
     return false;
   }
   mCDMCallback = aCDMCallback;
   mMainThread = aMainThread;
-  return SendInit(aAllowDistinctiveIdentifier, aAllowPersistentState);
+
+  if (SendInit(aAllowDistinctiveIdentifier, aAllowPersistentState)) {
+    return true;
+  }
+
+  RefPtr<gmp::GeckoMediaPluginService> service =
+    gmp::GeckoMediaPluginService::GetGeckoMediaPluginService();
+  bool xpcomWillShutdown = service && service->XPCOMWillShutdownReceived();
+  aOutFailureReason = nsPrintfCString(
+    "ChromiumCDMParent::Init() failed "
+    "shutdown=%d cdmCrash=%d actorDestroyed=%d browserShutdown=%d",
+    mIsShutdown,
+    mAbnormalShutdown,
+    mActorDestroyed,
+    xpcomWillShutdown);
+  return false;
 }
 
 void
@@ -865,11 +891,11 @@ ChromiumCDMParent::ActorDestroy(ActorDestroyReason aWhy)
     mContentParent->ChromiumCDMDestroyed(this);
     mContentParent = nullptr;
   }
-  bool abnormalShutdown = (aWhy == AbnormalShutdown);
-  if (abnormalShutdown && callback) {
+  mAbnormalShutdown = (aWhy == AbnormalShutdown);
+  if (mAbnormalShutdown && callback) {
     callback->Terminated();
   }
-  MaybeDisconnect(abnormalShutdown);
+  MaybeDisconnect(mAbnormalShutdown);
 }
 
 RefPtr<MediaDataDecoder::InitPromise>

dom/media/gmp/ChromiumCDMParent.h

@@ -43,7 +43,8 @@ public:
   bool Init(ChromiumCDMCallback* aCDMCallback,
             bool aAllowDistinctiveIdentifier,
             bool aAllowPersistentState,
-            nsIEventTarget* aMainThread);
+            nsIEventTarget* aMainThread,
+            nsCString& aOutFailureReason);
 
   void CreateSession(uint32_t aCreateSessionToken,
                      uint32_t aSessionType,
@@ -182,6 +183,7 @@ protected:
   bool mIsShutdown = false;
   bool mVideoDecoderInitialized = false;
   bool mActorDestroyed = false;
+  bool mAbnormalShutdown = false;
 
   // The H.264 decoder in Widevine CDM versions 970 and later output in decode
   // order rather than presentation order, so we reorder in presentation order

dom/media/gmp/ChromiumCDMProxy.cpp

@@ -101,13 +101,13 @@ ChromiumCDMProxy::Init(PromiseId aPromiseId,
         [self, aPromiseId](RefPtr<gmp::ChromiumCDMParent> cdm) {
           self->mCallback =
             MakeUnique<ChromiumCDMCallbackProxy>(self, self->mMainThread);
+          nsCString failureReason;
           if (!cdm->Init(self->mCallback.get(),
                          self->mDistinctiveIdentifierRequired,
                          self->mPersistentStateRequired,
-                         self->mMainThread)) {
-            self->RejectPromise(aPromiseId,
-                                NS_ERROR_FAILURE,
-                                NS_LITERAL_CSTRING("GetCDM failed due to CDM initialization failure."));
+                         self->mMainThread,
+                         failureReason)) {
+            self->RejectPromise(aPromiseId, NS_ERROR_FAILURE, failureReason);
             return;
           }
           {

dom/media/gmp/GMPService.cpp

@@ -150,6 +150,7 @@ GeckoMediaPluginService::GeckoMediaPluginService()
   : mMutex("GeckoMediaPluginService::mMutex")
   , mGMPThreadShutdown(false)
   , mShuttingDownOnGMPThread(false)
+  , mXPCOMWillShutdown(false)
 {
   MOZ_ASSERT(NS_IsMainThread());
 
@@ -224,6 +225,8 @@ GeckoMediaPluginService::Init()
   nsCOMPtr<nsIObserverService> obsService = mozilla::services::GetObserverService();
   MOZ_ASSERT(obsService);
   MOZ_ALWAYS_SUCCEEDS(obsService->AddObserver(this, NS_XPCOM_SHUTDOWN_THREADS_OBSERVER_ID, false));
+  MOZ_ALWAYS_SUCCEEDS(
+    obsService->AddObserver(this, NS_XPCOM_WILL_SHUTDOWN_OBSERVER_ID, false));
 
   // Kick off scanning for plugins
   nsCOMPtr<nsIThread> thread;

dom/media/gmp/GMPService.h

@@ -10,6 +10,7 @@
 #include "mozIGeckoMediaPluginService.h"
 #include "nsIObserver.h"
 #include "nsTArray.h"
+#include "mozilla/Atomics.h"
 #include "mozilla/Attributes.h"
 #include "mozilla/Monitor.h"
 #include "nsString.h"
@@ -107,6 +108,8 @@ public:
   void ConnectCrashHelper(uint32_t aPluginId, GMPCrashHelper* aHelper);
   void DisconnectCrashHelper(GMPCrashHelper* aHelper);
 
+  bool XPCOMWillShutdownReceived() const { return mXPCOMWillShutdown; }
+
 protected:
   GeckoMediaPluginService();
   virtual ~GeckoMediaPluginService();
@@ -135,6 +138,7 @@ protected:
   RefPtr<AbstractThread> mAbstractGMPThread;
   bool mGMPThreadShutdown;
   bool mShuttingDownOnGMPThread;
+  Atomic<bool> mXPCOMWillShutdown;
 
   nsClassHashtable<nsUint32HashKey, nsTArray<RefPtr<GMPCrashHelper>>> mPluginCrashHelpers;
 };

dom/media/gmp/GMPServiceChild.cpp

@@ -387,6 +387,8 @@ GeckoMediaPluginServiceChild::Observe(nsISupports* aSubject,
       mServiceChild = nullptr;
     }
     ShutdownGMPThread();
+  } else if (!strcmp(NS_XPCOM_WILL_SHUTDOWN_OBSERVER_ID, aTopic)) {
+    mXPCOMWillShutdown = true;
   }
 
   return NS_OK;

dom/media/gmp/GMPServiceParent.cpp

@@ -309,6 +309,8 @@ GeckoMediaPluginServiceParent::Observe(nsISupports* aSubject,
   } else if (!strcmp(NS_XPCOM_SHUTDOWN_THREADS_OBSERVER_ID, aTopic)) {
     MOZ_ASSERT(mShuttingDown);
     ShutdownGMPThread();
+  } else if (!strcmp(NS_XPCOM_WILL_SHUTDOWN_OBSERVER_ID, aTopic)) {
+    mXPCOMWillShutdown = true;
   } else if (!strcmp("last-pb-context-exited", aTopic)) {
     // When Private Browsing mode exits, all we need to do is clear
     // mTempNodeIds. This drops all the node ids we've cached in memory

dom/media/gtest/TestCDMStorage.cpp

@@ -465,7 +465,12 @@ class CDMStorageTest
                     self->mCDM = cdm;
                     EXPECT_TRUE(!!self->mCDM);
                     self->mCallback.reset(new CallbackProxy(self));
-                    self->mCDM->Init(self->mCallback.get(), false, true, GetMainThreadEventTarget());
+                    nsCString failureReason;
+                    self->mCDM->Init(self->mCallback.get(),
+                                     false,
+                                     true,
+                                     GetMainThreadEventTarget(),
+                                     failureReason);
 
                     for (auto& update : aUpdates) {
                       self->Update(update);