(Not ready for review!) Toolbar and views high dpi support.

content/browser/web_contents/web_contents_impl.cc

Index: content/browser/web_contents/web_contents_impl.cc
diff --git a/content/browser/web_contents/web_contents_impl.cc b/content/browser/web_contents/web_contents_impl.cc
index a11aa65fcf580ffea9ad443f3fc6250cfdb5f1dc..9e7a04cfbd96fe6cadbc9a6bf180ef23767a4a89 100644
--- a/content/browser/web_contents/web_contents_impl.cc
+++ b/content/browser/web_contents/web_contents_impl.cc
@@ -497,9 +497,15 @@ WebPreferences WebContentsImpl::GetWebkitPrefs(RenderViewHost* rvh,
   prefs.accelerated_compositing_enabled =
       GpuProcessHost::gpu_enabled() &&
       !command_line.HasSwitch(switches::kDisableAcceleratedCompositing);
+#if defined(OS_WIN) && defined(ENABLE_HIDPI)
+  prefs.force_compositing_mode = true;
+#else
   prefs.force_compositing_mode =
       content::IsForceCompositingModeEnabled() &&
       !command_line.HasSwitch(switches::kDisableForceCompositingMode);
+#endif
+//  prefs.fixed_position_compositing_enabled =
+//      command_line.HasSwitch(switches::kEnableCompositingForFixedPosition);
   prefs.accelerated_2d_canvas_enabled =
       GpuProcessHost::gpu_enabled() &&
       !command_line.HasSwitch(switches::kDisableAccelerated2dCanvas);
@@ -618,15 +624,21 @@ WebPreferences WebContentsImpl::GetWebkitPrefs(RenderViewHost* rvh,
 
   prefs.is_online = !net::NetworkChangeNotifier::IsOffline();
 
-  // Force accelerated compositing and 2d canvas off for chrome: and about:
-  // pages (unless it's specifically allowed).
-  if ((url.SchemeIs(chrome::kChromeUIScheme) ||
+#if defined(OS_WIN) && defined(ENABLE_HIDPI)
+  prefs.accelerated_compositing_enabled = true;
+  prefs.accelerated_2d_canvas_enabled = true;
+#else
+  // Force accelerated compositing and 2d canvas off for chrome:, about: and
+  // chrome-devtools: pages (unless it's specifically allowed).
+  if ((url.SchemeIs(chrome::kChromeDevToolsScheme) ||
+      url.SchemeIs(chrome::kChromeUIScheme) ||
       (url.SchemeIs(chrome::kAboutScheme) &&
        url.spec() != chrome::kAboutBlankURL)) &&
       !command_line.HasSwitch(switches::kAllowWebUICompositing)) {
     prefs.accelerated_compositing_enabled = false;
     prefs.accelerated_2d_canvas_enabled = false;
   }
+#endif
 
   if (url.SchemeIs(chrome::kChromeDevToolsScheme))
     prefs.show_fps_counter = false;