cc: Make OutputSurfaceFrame::sub_buffer_rect optional

content/browser/compositor/gpu_browser_compositor_output_surface.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/compositor/gpu_browser_compositor_output_surface.h"
 
 #include <utility>
 
 #include "build/build_config.h"
 #include "cc/output/output_surface_client.h"
@@ skipping 78 matching lines @@
     bool has_alpha,
     bool use_stencil) {
   context_provider()->ContextGL()->ResizeCHROMIUM(
       size.width(), size.height(), device_scale_factor, has_alpha);
 }
 
 void GpuBrowserCompositorOutputSurface::SwapBuffers(
     cc::OutputSurfaceFrame frame) {
   GetCommandBufferProxy()->SetLatencyInfo(frame.latency_info);
 
-  gfx::Rect swap_rect = frame.sub_buffer_rect;
   gfx::Size surface_size = frame.size;
   if (reflector_) {
-    if (swap_rect == gfx::Rect(surface_size)) {
+    if (frame.sub_buffer_rect) {
+      reflector_texture_->CopyTextureSubImage(*frame.sub_buffer_rect);
+      reflector_->OnSourcePostSubBuffer(*frame.sub_buffer_rect, surface_size);
+    } else {
       reflector_texture_->CopyTextureFullImage(surface_size);
       reflector_->OnSourceSwapBuffers(surface_size);
-    } else {
-      reflector_texture_->CopyTextureSubImage(swap_rect);
-      reflector_->OnSourcePostSubBuffer(swap_rect, surface_size);
     }
   }
 
-  if (swap_rect == gfx::Rect(frame.size))
+  if (frame.sub_buffer_rect) {
+    context_provider_->ContextSupport()->PartialSwapBuffers(
+        *frame.sub_buffer_rect);
+  } else {
     context_provider_->ContextSupport()->Swap();
-  else
-    context_provider_->ContextSupport()->PartialSwapBuffers(swap_rect);
+  }
 }
 
 uint32_t GpuBrowserCompositorOutputSurface::GetFramebufferCopyTextureFormat() {
   auto* gl = static_cast<ui::ContextProviderCommandBuffer*>(context_provider());
   return gl->GetCopyTextureInternalFormat();
 }
 
 bool GpuBrowserCompositorOutputSurface::IsDisplayedAsOverlayPlane() const {
   return false;
 }
@@ skipping 15 matching lines @@
 GpuBrowserCompositorOutputSurface::GetCommandBufferProxy() {
   ui::ContextProviderCommandBuffer* provider_command_buffer =
       static_cast<ui::ContextProviderCommandBuffer*>(context_provider_.get());
   gpu::CommandBufferProxyImpl* command_buffer_proxy =
       provider_command_buffer->GetCommandBufferProxy();
   DCHECK(command_buffer_proxy);
   return command_buffer_proxy;
 }
 
 }  // namespace content