Cache render targets that render to wrapped textures

src/gpu/GrSurface.cpp

Index: src/gpu/GrSurface.cpp
diff --git a/src/gpu/GrSurface.cpp b/src/gpu/GrSurface.cpp
index 886945c71036052812e3e0e003ad931b1dfd672d..b157cf2028612d87e872416726fe22ca3491cbd5 100644
--- a/src/gpu/GrSurface.cpp
+++ b/src/gpu/GrSurface.cpp
@@ -19,17 +19,20 @@ size_t GrSurface::WorseCaseSize(const GrSurfaceDesc& desc) {
 
     bool isRenderTarget = SkToBool(desc.fFlags & kRenderTarget_GrSurfaceFlag);
     if (isRenderTarget) {
+        // We own one color value for texture storing the rendering result,
+        // e.g. the actual fbo texture attachment or the resolve texture.
         // We own one color value for each MSAA sample.
-        int colorValuesPerPixel = SkTMax(1, desc.fSampleCnt);
-        if (desc.fSampleCnt) {
-            // Worse case, we own the resolve buffer so that is one more sample per pixel.
-            colorValuesPerPixel += 1;
-        }
+        size_t colorValues = 1 + static_cast<size_t>(desc.fSampleCnt);
+
         SkASSERT(kUnknown_GrPixelConfig != desc.fConfig);
         SkASSERT(!GrPixelConfigIsCompressed(desc.fConfig));
         size_t colorBytes = GrBytesPerPixel(desc.fConfig);
         SkASSERT(colorBytes > 0);
-        size = colorValuesPerPixel * desc.fWidth * desc.fHeight * colorBytes;
+        size_t bytesPerColorValue = desc.fWidth * desc.fHeight * colorBytes;
+        size = colorValues * bytesPerColorValue;
+        // Render target that is a texture might have mipmaps in the
+        // rendering target texture.
+        size += bytesPerColorValue / 3;
     } else {
         if (GrPixelConfigIsCompressed(desc.fConfig)) {
             size = GrCompressedFormatDataSize(desc.fConfig, desc.fWidth, desc.fHeight);