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

chrome/browser/ui/webui/chrome_web_ui_factory.cc

Index: chrome/browser/ui/webui/chrome_web_ui_factory.cc
diff --git a/chrome/browser/ui/webui/chrome_web_ui_factory.cc b/chrome/browser/ui/webui/chrome_web_ui_factory.cc
index 4df28b05e87d620f279f8f69ee162ea957a81cbc..34612f67ef2b0aeba9f9b31a9a209d46911e65c6 100644
--- a/chrome/browser/ui/webui/chrome_web_ui_factory.cc
+++ b/chrome/browser/ui/webui/chrome_web_ui_factory.cc
@@ -25,6 +25,7 @@
 #include "chrome/browser/ui/webui/history2_ui.h"
 #include "chrome/browser/ui/webui/history_ui.h"
 #include "chrome/browser/ui/webui/html_dialog_ui.h"
+#include "chrome/browser/ui/webui/hung_renderer_dialog_ui.h"
 #include "chrome/browser/ui/webui/media/media_internals_ui.h"
 #include "chrome/browser/ui/webui/net_internals_ui.h"
 #include "chrome/browser/ui/webui/ntp/new_tab_ui.h"
@@ -68,14 +69,10 @@
 #include "chrome/browser/ui/webui/conflicts_ui.h"
 #endif
 
-#if defined(WEBUI_DIALOGS) && defined(OS_POSIX) && !defined(OS_MACOSX)
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
 #include "chrome/browser/ui/webui/certificate_viewer_ui.h"
 #endif
 
-#if defined(WEBUI_DIALOGS)
-#include "chrome/browser/ui/webui/hung_renderer_dialog_ui.h"
-#endif
-
 namespace {
 
 // A function for creating a new WebUI. The caller owns the return value, which
@@ -150,15 +147,13 @@ static WebUIFactoryFunction GetWebUIFactoryFunction(Profile* profile,
     return &NewWebUI<BookmarksUI>;
   if (url.host() == chrome::kChromeUIBugReportHost)
     return &NewWebUI<BugReportUI>;
-#if defined(WEBUI_DIALOGS) && defined(OS_POSIX) && !defined(OS_MACOSX)
+#if defined(OS_POSIX) && !defined(OS_MACOSX)
   if (url.host() == chrome::kChromeUICertificateViewerHost)
     return &NewWebUI<CertificateViewerUI>;
 #endif
-#if defined(WEBUI_DIALOGS)
   if (url.host() == chrome::kChromeUIHungRendererDialogHost) {
     return &NewWebUI<HungRendererDialogUI>;
   }
-#endif
   if (url.host() == chrome::kChromeUICrashesHost)
     return &NewWebUI<CrashesUI>;
   if (url.host() == chrome::kChromeUIDevToolsHost)