Enable web components for shell windows based on their render view type, rather than their origin.

chrome/renderer/chrome_render_view_observer.cc

Index: chrome/renderer/chrome_render_view_observer.cc
diff --git a/chrome/renderer/chrome_render_view_observer.cc b/chrome/renderer/chrome_render_view_observer.cc
index ec514b4618a26c1d08db60ec447962ff34dd8312..f10a28cc8e167d1b3496986f96f4c9688745dd58 100644
--- a/chrome/renderer/chrome_render_view_observer.cc
+++ b/chrome/renderer/chrome_render_view_observer.cc
@@ -22,6 +22,7 @@
 #include "chrome/renderer/chrome_render_process_observer.h"
 #include "chrome/renderer/content_settings_observer.h"
 #include "chrome/renderer/extensions/dispatcher.h"
+#include "chrome/renderer/extensions/extension_helper.h"
 #include "chrome/renderer/external_host_bindings.h"
 #include "chrome/renderer/frame_sniffer.h"
 #include "chrome/renderer/prerender/prerender_helper.h"
@@ -530,6 +531,15 @@ bool ChromeRenderViewObserver::allowWebComponents(const WebDocument& document,
 
     if (extension->HasAPIPermission(APIPermission::kExperimental))
       return true;
+  } else {
+    // XXX perhaps we should only use this check, and remove the above checks?

[Mihai Parparita -not on Chrome, 2012/09/13 20:17:36]

I'd rather keep the permission-based checks where possible, since they document
intent better.

This should have a comment saying that it covers the shell window/custom
titlebar scenario.

+    extensions::ExtensionHelper* helper =
+        extensions::ExtensionHelper::Get(render_view());
+    // XXX is there always an ExtensionHelper for every RenderView?

[Mihai Parparita -not on Chrome, 2012/09/13 20:17:36]

Yes. We create one as soon as the RenderView is created:
http://code.google.com/searchframe#OAMlx_jo-ck/src/chrome/renderer/chrome_con...

+    // chrome/renderer/chrome_content_renderer_client.cc seems to make this
+    // assumption...
+    if (helper->view_type() == chrome::VIEW_TYPE_APP_SHELL)
+      return true;
   }
 
   return false;