Expose UpdateOffscreenFrameBufferSize from GLES2Decoder to allow Mac...

gpu/command_buffer/service/gpu_processor_mac.cc

Index: gpu/command_buffer/service/gpu_processor_mac.cc
===================================================================
--- gpu/command_buffer/service/gpu_processor_mac.cc	(revision 48748)
+++ gpu/command_buffer/service/gpu_processor_mac.cc	(working copy)
@@ -71,6 +71,7 @@
 uint64 GPUProcessor::SetWindowSizeForIOSurface(const gfx::Size& size) {
 #if !defined(UNIT_TEST)
   ResizeOffscreenFrameBuffer(size);
+  decoder_->UpdateOffscreenFrameBufferSize();
   return surface_->SetSurfaceSize(size);
 #else
   return 0;
@@ -81,6 +82,7 @@
     const gfx::Size& size) {
 #if !defined(UNIT_TEST)
   ResizeOffscreenFrameBuffer(size);
+  decoder_->UpdateOffscreenFrameBufferSize();
   return surface_->SetTransportDIBSize(size);
 #else
   return TransportDIB::DefaultHandleValue();