Bug 858039 - Initialize the correct mType for SurfaceStream_TripleBuffer_Async. r=snorp

gfx/gl/GLScreenBuffer.cpp

@@ -315,7 +315,7 @@ GLScreenBuffer::Morph(SurfaceFactory_GL* newFactory, SurfaceStreamType streamTyp
         mFactory = newFactory;
     }
 
-    if (mStream->Type() == streamType)
+    if (mStream->mType == streamType)
         return;
 
     SurfaceStream* newStream = SurfaceStream::CreateForType(streamType, mStream);

gfx/gl/SurfaceStream.cpp

@@ -351,12 +351,7 @@ SurfaceStream_TripleBuffer_Copy::SwapConsumer_NoWait()
     return mConsumer;
 }
 
-
-
-SurfaceStream_TripleBuffer::SurfaceStream_TripleBuffer(SurfaceStream* prevStream)
-    : SurfaceStream(SurfaceStreamType::TripleBuffer, prevStream)
-    , mStaging(nullptr)
-    , mConsumer(nullptr)
+void SurfaceStream_TripleBuffer::Init(SurfaceStream* prevStream)
 {
     if (!prevStream)
         return;
@@ -372,6 +367,23 @@ SurfaceStream_TripleBuffer::SurfaceStream_TripleBuffer(SurfaceStream* prevStream
     mConsumer = Absorb(prevConsumer);
 }
 
+
+SurfaceStream_TripleBuffer::SurfaceStream_TripleBuffer(SurfaceStreamType type, SurfaceStream* prevStream)
+    : SurfaceStream(type, prevStream)
+    , mStaging(nullptr)
+    , mConsumer(nullptr)
+{
+    SurfaceStream_TripleBuffer::Init(prevStream);
+}
+
+SurfaceStream_TripleBuffer::SurfaceStream_TripleBuffer(SurfaceStream* prevStream)
+    : SurfaceStream(SurfaceStreamType::TripleBuffer, prevStream)
+    , mStaging(nullptr)
+    , mConsumer(nullptr)
+{
+    SurfaceStream_TripleBuffer::Init(prevStream);
+}
+
 SurfaceStream_TripleBuffer::~SurfaceStream_TripleBuffer()
 {
     Delete(mStaging);
@@ -431,9 +443,8 @@ SurfaceStream_TripleBuffer::SwapConsumer_NoWait()
 }
 
 SurfaceStream_TripleBuffer_Async::SurfaceStream_TripleBuffer_Async(SurfaceStream* prevStream)
-    : SurfaceStream_TripleBuffer(prevStream)
+    : SurfaceStream_TripleBuffer(SurfaceStreamType::TripleBuffer_Async, prevStream)
 {
-    mType = SurfaceStreamType::TripleBuffer_Async;
 }
 
 SurfaceStream_TripleBuffer_Async::~SurfaceStream_TripleBuffer_Async()

gfx/gl/SurfaceStream.h

@@ -41,11 +41,10 @@ public:
         return (SurfaceStream*)handle;
     }
 
-    SurfaceStreamType Type() { return mType; }
+    const SurfaceStreamType mType;
 protected:
     // |mProd| is owned by us, but can be ripped away when
     // creating a new GLStream from this one.
-    SurfaceStreamType mType;
     SharedSurface* mProducer;
     std::set<SharedSurface*> mSurfaces;
     std::stack<SharedSurface*> mScraps;
@@ -60,7 +59,7 @@ protected:
         , mMonitor("SurfaceStream monitor")
         , mIsAlive(true)
     {
-        MOZ_ASSERT(!prevStream || mType != prevStream->Type(),
+        MOZ_ASSERT(!prevStream || mType != prevStream->mType,
                    "We should not need to create a SurfaceStream from another "
                    "of the same type.");
     }
@@ -175,10 +174,18 @@ protected:
     // Returns true if we were able to wait, false if not
     virtual bool WaitForCompositor() { return false; }
 
+    // To support subclasses initializing the mType.
+    SurfaceStream_TripleBuffer(SurfaceStreamType type, SurfaceStream* prevStream);
+
 public:
     SurfaceStream_TripleBuffer(SurfaceStream* prevStream);
     virtual ~SurfaceStream_TripleBuffer();
 
+private:
+    // Common constructor code.
+    void Init(SurfaceStream* prevStream);
+
+public:
     // Done writing to prod, swap prod and staging
     virtual SharedSurface* SwapProducer(SurfaceFactory* factory,
                                         const gfxIntSize& size);