Bug 1400407 - Part 3: Remove IsMirror concept, as it is no longer used by WebVR,r=jgilbert

- This patch is the same as one from Bug 1382104 (Remove IsMirror concept
  in favor of checking forwarder).
- It is safe to uplift this patch without the rest of Bug 1382104 as long
  as the remaining Bug 1381084 is also uplifted.

MozReview-Commit-ID: 21YZObeSUa3

--HG--
extra : rebase_source : 8d543fe69f4ac9df5ccdc42d3ce47bb37eea4396

dom/canvas/WebGLContext.cpp

@@ -114,7 +114,6 @@ WebGLContext::WebGLContext()
     , mBufferFetchingHasPerVertex(false)
     , mMaxFetchedVertices(0)
     , mMaxFetchedInstances(0)
-    , mLayerIsMirror(false)
     , mBypassShaderValidation(false)
     , mEmptyTFO(0)
     , mContextLossHandler(this)
@@ -1278,7 +1277,6 @@ WebGLContext::UpdateLastUseIndex()
 }
 
 static uint8_t gWebGLLayerUserData;
-static uint8_t gWebGLMirrorLayerUserData;
 
 class WebGLContextUserData : public LayerUserData
 {
@@ -1314,11 +1312,11 @@ private:
 already_AddRefed<layers::Layer>
 WebGLContext::GetCanvasLayer(nsDisplayListBuilder* builder,
                              Layer* oldLayer,
-                             LayerManager* manager,
-                             bool aMirror /*= false*/)
+                             LayerManager* manager)
 {
     if (!mResetLayer && oldLayer &&
-        oldLayer->HasUserData(aMirror ? &gWebGLMirrorLayerUserData : &gWebGLLayerUserData)) {
+        oldLayer->HasUserData(&gWebGLLayerUserData))
+    {
         RefPtr<layers::Layer> ret = oldLayer;
         return ret.forget();
     }
@@ -1330,38 +1328,33 @@ WebGLContext::GetCanvasLayer(nsDisplayListBuilder* builder,
     }
 
     WebGLContextUserData* userData = nullptr;
-    if (builder->IsPaintingToWindow() && mCanvasElement && !aMirror) {
+    if (builder->IsPaintingToWindow() && mCanvasElement) {
         userData = new WebGLContextUserData(mCanvasElement);
     }
 
-    canvasLayer->SetUserData(aMirror ? &gWebGLMirrorLayerUserData : &gWebGLLayerUserData, userData);
+    canvasLayer->SetUserData(&gWebGLLayerUserData, userData);
 
     CanvasRenderer* canvasRenderer = canvasLayer->CreateOrGetCanvasRenderer();
-    if (!InitializeCanvasRenderer(builder, canvasRenderer, aMirror))
+    if (!InitializeCanvasRenderer(builder, canvasRenderer))
       return nullptr;
 
     uint32_t flags = gl->Caps().alpha ? 0 : Layer::CONTENT_OPAQUE;
     canvasLayer->SetContentFlags(flags);
 
     mResetLayer = false;
-    // We only wish to update mLayerIsMirror when a new layer is returned.
-    // If a cached layer is returned above, aMirror is not changing since
-    // the last cached layer was created and mLayerIsMirror is still valid.
-    mLayerIsMirror = aMirror;
 
     return canvasLayer.forget();
 }
 
 bool
 WebGLContext::InitializeCanvasRenderer(nsDisplayListBuilder* aBuilder,
-                                       CanvasRenderer* aRenderer,
-                                       bool aMirror)
+                                       CanvasRenderer* aRenderer)
 {
     if (IsContextLost())
         return false;
 
     CanvasInitializeData data;
-    if (aBuilder->IsPaintingToWindow() && mCanvasElement && !aMirror) {
+    if (aBuilder->IsPaintingToWindow() && mCanvasElement) {
         // Make the layer tell us whenever a transaction finishes (including
         // the current transaction), so we can clear our invalidation state and
         // start invalidating again. We need to do this for the layer that is
@@ -1384,7 +1377,6 @@ WebGLContext::InitializeCanvasRenderer(nsDisplayListBuilder* aBuilder,
     data.mSize = nsIntSize(mWidth, mHeight);
     data.mHasAlpha = gl->Caps().alpha;
     data.mIsGLAlphaPremult = IsPremultAlpha() || !data.mHasAlpha;
-    data.mIsMirror = aMirror;
 
     aRenderer->Initialize(data);
     aRenderer->SetDirty();
@@ -2351,7 +2343,7 @@ WebGLContext::GetVRFrame()
       return nullptr;
   }
 
-  return sharedSurface.forget();
+    return sharedSurface.forget();
 }
 
 ////////////////////////////////////////////////////////////////////////////////

dom/canvas/WebGLContext.h

@@ -1435,7 +1435,6 @@ protected:
     bool mInvalidated;
     bool mCapturedFrameInvalidated;
     bool mResetLayer;
-    bool mLayerIsMirror;
     bool mOptionsFrozen;
     bool mDisableExtensions;
     bool mIsMesa;

gfx/layers/CanvasRenderer.h

@@ -41,7 +41,6 @@ struct CanvasInitializeData {
     , mSize(0,0)
     , mHasAlpha(false)
     , mIsGLAlphaPremult(true)
-    , mIsMirror(false)
   { }
 
   // One of these three must be specified for Canvas2D, but never more than one
@@ -66,10 +65,6 @@ struct CanvasInitializeData {
 
   // Whether mGLContext contains data that is alpha-premultiplied.
   bool mIsGLAlphaPremult;
-
-  // Whether the canvas front buffer is already being rendered somewhere else.
-  // When true, do not swap buffers or Morph() to another factory on mGLContext
-  bool mIsMirror;
 };
 
 // Based class which used for canvas rendering. There are many derived classes for

gfx/layers/CopyableCanvasRenderer.cpp

@@ -39,7 +39,6 @@ CopyableCanvasRenderer::CopyableCanvasRenderer()
   , mAsyncRenderer(nullptr)
   , mIsAlphaPremultiplied(true)
   , mOriginPos(gl::OriginPos::TopLeft)
-  , mIsMirror(false)
   , mOpaque(true)
   , mCachedTempSurface(nullptr)
 {
@@ -61,7 +60,6 @@ CopyableCanvasRenderer::Initialize(const CanvasInitializeData& aData)
     mGLContext = aData.mGLContext;
     mIsAlphaPremultiplied = aData.mIsGLAlphaPremult;
     mOriginPos = gl::OriginPos::BottomLeft;
-    mIsMirror = aData.mIsMirror;
 
     MOZ_ASSERT(mGLContext->IsOffscreen(), "canvas gl context isn't offscreen");
 

gfx/layers/CopyableCanvasRenderer.h

@@ -62,7 +62,6 @@ protected:
 
   bool mIsAlphaPremultiplied;
   gl::OriginPos mOriginPos;
-  bool mIsMirror;
 
   bool mOpaque;
 

gfx/layers/ShareableCanvasRenderer.cpp

@@ -62,7 +62,7 @@ ShareableCanvasRenderer::Initialize(const CanvasInitializeData& aData)
   UniquePtr<gl::SurfaceFactory> factory =
     gl::GLScreenBuffer::CreateFactory(mGLContext, caps, forwarder, mFlags);
 
-  if (mGLFrontbuffer || aData.mIsMirror) {
+  if (mGLFrontbuffer) {
     // We're using a source other than the one in the default screen.
     // (SkiaGL)
     mFactory = Move(factory);

gfx/layers/client/CanvasClient.cpp

@@ -410,11 +410,6 @@ CanvasClientSharedSurface::UpdateRenderer(gfx::IntSize aSize, Renderer& aRendere
       gfxCriticalError() << "Invalid canvas front buffer";
       return;
     }
-  } else if (canvasRenderer && canvasRenderer->mIsMirror) {
-    mShSurfClient = CloneSurface(gl->Screen()->Front()->Surf(), canvasRenderer->mFactory.get());
-    if (!mShSurfClient) {
-      return;
-    }
   } else {
     mShSurfClient = gl->Screen()->Front();
     if (mShSurfClient && mShSurfClient->GetAllocator() &&