app-shell: Introduce a ShellRendererMainDelegate.

apps/shell/renderer/shell_content_renderer_client.h

Index: apps/shell/renderer/shell_content_renderer_client.h
diff --git a/apps/shell/renderer/shell_content_renderer_client.h b/apps/shell/renderer/shell_content_renderer_client.h
index 506704c6939b81fab9391602c72d7f28420ed480..9f7aee2e227a9a1a5059e8f9f3f20a0a01c7d640 100644
--- a/apps/shell/renderer/shell_content_renderer_client.h
+++ b/apps/shell/renderer/shell_content_renderer_client.h
@@ -19,11 +19,13 @@ namespace apps {
 
 class ShellExtensionsClient;
 class ShellExtensionsRendererClient;
+class ShellRendererMainDelegate;
 
 // Renderer initialization and runtime support for app_shell.
 class ShellContentRendererClient : public content::ContentRendererClient {
  public:
-  ShellContentRendererClient();
+  explicit ShellContentRendererClient(
+      scoped_ptr<ShellRendererMainDelegate> delegate);
   virtual ~ShellContentRendererClient();
 
   // content::ContentRendererClient implementation:
@@ -42,6 +44,7 @@ class ShellContentRendererClient : public content::ContentRendererClient {
   virtual bool ShouldEnableSiteIsolationPolicy() const OVERRIDE;
 
  private:
+  scoped_ptr<ShellRendererMainDelegate> delegate_;
   scoped_ptr<ShellExtensionsClient> extensions_client_;
   scoped_ptr<ShellExtensionsRendererClient> extensions_renderer_client_;
   scoped_ptr<extensions::DispatcherDelegate> extension_dispatcher_delegate_;