Content shell: Javascript dialogs, first pass, just Mac for now.

content/shell/shell.cc

Index: content/shell/shell.cc
diff --git a/content/shell/shell.cc b/content/shell/shell.cc
index 49097bc36257f6a3e8a5ce177fd7655b543838ae..2e9c8adceb8eeac3a9a4b2f48ef72e2af0911844 100644
--- a/content/shell/shell.cc
+++ b/content/shell/shell.cc
@@ -11,6 +11,7 @@
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/render_view_host.h"
 #include "content/public/browser/web_contents.h"
+#include "content/shell/shell_js_dialog_creator.h"
 #include "content/shell/shell_messages.h"
 #include "content/shell/shell_switches.h"
 #include "ui/gfx/size.h"
@@ -141,6 +142,15 @@ void Shell::DidNavigateMainFramePostCommit(WebContents* tab) {
   PlatformSetAddressBarURL(tab->GetURL());
 }
 
+JavaScriptDialogCreator* Shell::GetJavaScriptDialogCreator() {
+  if (CommandLine::ForCurrentProcess()->HasSwitch(switches::kDumpRenderTree))
+    return NULL;
+
+  if (!dialog_creator_.get())
+    dialog_creator_.reset(new ShellJavaScriptDialogCreator());
+  return dialog_creator_.get();
+}
+
 void Shell::DidFinishLoad(int64 frame_id,
                           const GURL& validated_url,
                           bool is_main_frame) {