Add --use-more-webui runtime flag to toggle WebUI replacements for native dialogs.

chrome/browser/ui/cocoa/hung_renderer_controller.mm

Index: chrome/browser/ui/cocoa/hung_renderer_controller.mm
diff --git a/chrome/browser/ui/cocoa/hung_renderer_controller.mm b/chrome/browser/ui/cocoa/hung_renderer_controller.mm
index f8dc950ee030000d58a08d8b9cad86149be462c3..ee8a6bb78b4333c1b7f3ab936b304bc8e282e100 100644
--- a/chrome/browser/ui/cocoa/hung_renderer_controller.mm
+++ b/chrome/browser/ui/cocoa/hung_renderer_controller.mm
@@ -181,7 +181,7 @@ HungRendererController* g_instance = NULL;
 
 namespace browser {
 
-void ShowHungRendererDialog(TabContents* contents) {
+void ShowNativeHungRendererDialog(TabContents* contents) {
   if (!logging::DialogsAreSuppressed()) {
     if (!g_instance)
       g_instance = [[HungRendererController alloc]
@@ -190,7 +190,7 @@ void ShowHungRendererDialog(TabContents* contents) {
   }
 }
 
-void HideHungRendererDialog(TabContents* contents) {
+void HideNativeHungRendererDialog(TabContents* contents) {
   if (!logging::DialogsAreSuppressed() && g_instance)
     [g_instance endForTabContents:contents];
 }