[content shell] change how the main render view is picked for layout tests

content/shell/shell_render_process_observer.h

Index: content/shell/shell_render_process_observer.h
diff --git a/content/shell/shell_render_process_observer.h b/content/shell/shell_render_process_observer.h
index 42d2ccadeab722c772f55cbe12d2329d5fd60ae8..505c6e0c398fcf855d849201980010ce52e5b776 100644
--- a/content/shell/shell_render_process_observer.h
+++ b/content/shell/shell_render_process_observer.h
@@ -38,6 +38,9 @@ class ShellRenderProcessObserver : public RenderProcessObserver {
   virtual void WebKitInitialized() OVERRIDE;
   virtual bool OnControlMessageReceived(const IPC::Message& message) OVERRIDE;
 
+  WebTestRunner::WebTestDelegate* test_delegate() const {
+    return test_delegate_;
+  }
   WebTestRunner::WebTestInterfaces* test_interfaces() const {
     return test_interfaces_.get();
   }
@@ -47,6 +50,7 @@ class ShellRenderProcessObserver : public RenderProcessObserver {
   void OnResetAll();
 
   scoped_ptr<WebTestRunner::WebTestInterfaces> test_interfaces_;
+  RenderView* main_render_view_;
   WebTestRunner::WebTestDelegate* test_delegate_;
 
   DISALLOW_COPY_AND_ASSIGN(ShellRenderProcessObserver);