Bug 1314884. Part 1 - move the calculation of seek target into DormantState::Enter() so we don't need to pass a SeekJob to the function. r=kaku

MozReview-Commit-ID: FyFp509dxwl

--HG--
extra : rebase_source : 4d6d229de4871d11b690b28b5b96463cc3b27973
extra : source : 9d718f819b6a79b67b0125972b8419b99021b75f

dom/media/MediaDecoderStateMachine.cpp

@@ -403,12 +403,22 @@ class MediaDecoderStateMachine::DormantState
 public:
   explicit DormantState(Master* aPtr) : StateObject(aPtr) {}
 
-  void Enter(SeekJob aPendingSeek)
+  void Enter()
   {
-    mPendingSeek = Move(aPendingSeek);
     if (mMaster->IsPlaying()) {
       mMaster->StopPlayback();
     }
+
+    // Calculate the position to seek to when exiting dormant.
+    auto t = mMaster->mMediaSink->IsStarted()
+      ? mMaster->GetClock()
+      : mMaster->GetMediaTime();
+    mPendingSeek.mTarget = SeekTarget(
+      t, SeekTarget::Accurate, MediaDecoderEventVisibility::Suppressed);
+    // SeekJob asserts |mTarget.IsValid() == !mPromise.IsEmpty()| so we
+    // need to create the promise even it is not used at all.
+    RefPtr<MediaDecoder::SeekPromise> x = mPendingSeek.mPromise.Ensure(__func__);
+
     mMaster->Reset();
     mMaster->mReader->ReleaseResources();
   }
@@ -686,16 +696,7 @@ private:
 
   void EnterDormant()
   {
-    auto t = mMaster->mMediaSink->IsStarted()
-      ? mMaster->GetClock()
-      : mMaster->GetMediaTime();
-    SeekJob seekJob;
-    seekJob.mTarget = SeekTarget(t, SeekTarget::Accurate,
-                                 MediaDecoderEventVisibility::Suppressed);
-    // SeekJob asserts |mTarget.IsValid() == !mPromise.IsEmpty()| so we
-    // need to create the promise even it is not used at all.
-    RefPtr<MediaDecoder::SeekPromise> unused = seekJob.mPromise.Ensure(__func__);
-    SetState<DormantState>(Move(seekJob));
+    SetState<DormantState>();
   }
 
   void StartDormantTimer()