Bug 1186236 - Fix drawQuad culling bug. r=nical

Consider the render target size for drawQuad culling.

gfx/layers/opengl/CompositorOGL.cpp

@@ -451,6 +451,8 @@ CompositorOGL::PrepareViewport(CompositingRenderTargetOGL* aRenderTarget)
   // Set the viewport correctly.
   mGLContext->fViewport(0, 0, size.width, size.height);
 
+  mRenderBound = Rect(0, 0, size.width, size.height);
+
   mViewportSize = size;
 
   if (!aRenderTarget->HasComplexProjection()) {
@@ -629,8 +631,6 @@ CompositorOGL::BeginFrame(const nsIntRegion& aInvalidRegion,
     *aRenderBoundsOut = rect;
   }
 
-  mRenderBoundsOut = rect;
-
   GLint width = rect.width;
   GLint height = rect.height;
 
@@ -989,7 +989,7 @@ CompositorOGL::DrawQuad(const Rect& aRect,
   // Do a simple culling if this rect is out of target buffer.
   // Inflate a small size to avoid some numerical imprecision issue.
   destRect.Inflate(1, 1);
-  if (!mRenderBoundsOut.Intersects(destRect)) {
+  if (!mRenderBound.Intersects(destRect)) {
     return;
   }
 

gfx/layers/opengl/CompositorOGL.h

@@ -457,7 +457,7 @@ private:
   FenceHandle mReleaseFenceHandle;
   ShaderProgramOGL *mCurrentProgram;
 
-  gfx::Rect mRenderBoundsOut;
+  gfx::Rect mRenderBound;
 
   CompositorOGLVRObjects mVR;
 };