Transfer theme & page background colors between changes of RWHV.

content/browser/renderer_host/render_widget_host_view_aura.cc

 // Copyright (c) 2012 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/renderer_host/render_widget_host_view_aura.h"
 
 #include <set>
 #include <utility>
 
 #include "base/auto_reset.h"
@@ skipping 1043 matching lines @@
   legacy_render_widget_host_HWND_ = NULL;
   legacy_window_destroyed_ = true;
 }
 #endif
 
 void RenderWidgetHostViewAura::OnSwapCompositorFrame(
     uint32_t output_surface_id,
     std::unique_ptr<cc::CompositorFrame> frame) {
   TRACE_EVENT0("content", "RenderWidgetHostViewAura::OnSwapCompositorFrame");
 
+  // Override the background color to the current compositor background.
+  // This allows us to, when navigating to a new page, transfer this color
+  // (via code in ContentsWebView) between the current RenderWidgetHost and
+  // the new one, avoiding a flash of the theme color in between.
+  // See crbug.com/470669.
+  // Setting the page's background color here should also have better quality
+  // output in cases when the window's root layer peeks out from the content
+  // layers.
+  SetBackgroundColor(frame->metadata.root_background_color);
+
   last_scroll_offset_ = frame->metadata.root_scroll_offset;
   if (!frame->delegated_frame_data)
     return;
 
   cc::ViewportSelection selection = frame->metadata.selection;
   if (IsUseZoomForDSFEnabled()) {
     float viewportToDIPScale = 1.0f / current_device_scale_factor_;
     selection.start.edge_top.Scale(viewportToDIPScale);
     selection.start.edge_bottom.Scale(viewportToDIPScale);
     selection.end.edge_top.Scale(viewportToDIPScale);
@@ skipping 1881 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // RenderWidgetHostViewBase, public:
 
 // static
 void RenderWidgetHostViewBase::GetDefaultScreenInfo(WebScreenInfo* results) {
   GetScreenInfoForWindow(results, NULL);
 }
 
 }  // namespace content