Fix gpu memory accounting for auto-resolving MSAA.

src/gpu/gl/GrGLRenderTarget.cpp

 /*
  * Copyright 2011 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "GrGLRenderTarget.h"
 
 #include "GrGLGpu.h"
@@ skipping 25 matching lines @@
     fViewport.fLeft   = 0;
     fViewport.fBottom = 0;
     fViewport.fWidth  = desc.fWidth;
     fViewport.fHeight = desc.fHeight;
 
     // We own one color value for each MSAA sample.
     fColorValuesPerPixel = SkTMax(1, fDesc.fSampleCnt);
     if (fTexFBOID != fRTFBOID) {
         // If we own the resolve buffer then that is one more sample per pixel.
         fColorValuesPerPixel += 1;
-    } 
+    } else if (fTexFBOID != 0) {
+        // For auto-resolving FBOs, the MSAA buffer is free.
+        fColorValuesPerPixel = 1;

[bsalomon, 2015/04/30 17:34:28]

looks ok to me, but can we rename this to something like
fColorSamplesForSizeComputation or something that makes it more clear that this
is really about byte size computation and not logical sample count? Or, we could
just compute the total size here and store that instead of the sample cnt. I
think it didn't work that way in the past because we didn't yet know whether we
had a stencil buffer. However, this class no longer has to account for the
stencil's memory

+    }
 }
 
 size_t GrGLRenderTarget::onGpuMemorySize() const {
     SkASSERT(kUnknown_GrPixelConfig != fDesc.fConfig);
     SkASSERT(!GrPixelConfigIsCompressed(fDesc.fConfig));
     size_t colorBytes = GrBytesPerPixel(fDesc.fConfig);
     SkASSERT(colorBytes > 0);
     return fColorValuesPerPixel * fDesc.fWidth * fDesc.fHeight * colorBytes;
 }
 
@@ skipping 16 matching lines @@
     INHERITED::onRelease();
 }
 
 void GrGLRenderTarget::onAbandon() {
     fRTFBOID                = 0;
     fTexFBOID               = 0;
     fMSColorRenderbufferID  = 0;
     fIsWrapped              = false;
     INHERITED::onAbandon();
 }