Avoid calling the GetSystemMetrics API in the renderer process on Windows to get the scrollbar metr…

content/renderer/render_view_win.cc

 // Copyright (c) 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/public/common/renderer_preferences.h"
+#include "content/child/webthemeengine_impl_default.h"
 #include "content/renderer/render_view_impl.h"
 #include "third_party/WebKit/public/web/win/WebFontRendering.h"
 #include "ui/gfx/font_render_params.h"
 
 using blink::WebFontRendering;
 
 namespace content {
 
 void RenderViewImpl::UpdateFontRenderingFromRendererPrefs() {
   const RendererPreferences& prefs = renderer_preferences_;
@@ skipping 10 matching lines @@
       prefs.status_font_family_name.c_str(), prefs.status_font_height);
 
   blink::WebFontRendering::setLCDOrder(
       gfx::FontRenderParams::SubpixelRenderingToSkiaLCDOrder(
           prefs.subpixel_rendering));
   blink::WebFontRendering::setLCDOrientation(
       gfx::FontRenderParams::SubpixelRenderingToSkiaLCDOrientation(
           prefs.subpixel_rendering));
 }
 
+void RenderViewImpl::UpdateThemePrefs() {
+  WebThemeEngineImpl::SetVerticalScrollbarWidth(
+      renderer_preferences_.vertical_scroll_bar_width_in_dips);
+  WebThemeEngineImpl::SetHorizontalScrollbarHeight(
+      renderer_preferences_.horizontal_scroll_bar_height_in_dips);
+  WebThemeEngineImpl::SetVerticalArrowBitmapHeight(
+      renderer_preferences_.arrow_bitmap_height_vertical_scroll_bar_in_dips);
+  WebThemeEngineImpl::SetHorizontalArrowBitmapWidth(
+      renderer_preferences_.arrow_bitmap_width_horizontal_scroll_bar_in_dips);

[brucedawson, 2015/04/03 17:00:24]

It seems clumsy having four different setter functions, four variables to store
the results, etc. A single function with four parameters would arguably be
better. A single function that takes a four-element struct would probably be
ideal - one function, one variable declaration. Using a four-element struct
instead of four functions/variables also makes extending this in the future far
simpler. But if we drop to just using SM_CXVSCROLL then this becomes irrelevant.

[ananta, 2015/04/03 19:17:04]

Done.

+}
+
 }  // namespace content