Fix for WebView accessible resources.

extensions/browser/guest_view/web_view/web_view_guest.h

Index: extensions/browser/guest_view/web_view/web_view_guest.h
diff --git a/extensions/browser/guest_view/web_view/web_view_guest.h b/extensions/browser/guest_view/web_view/web_view_guest.h
index 9605ad26df449fff635779928dbc221c2f5f664a..1ab59d7da83ec1e1267528cdcecedf7a4df170b2 100644
--- a/extensions/browser/guest_view/web_view/web_view_guest.h
+++ b/extensions/browser/guest_view/web_view/web_view_guest.h
@@ -60,6 +60,12 @@ class WebViewGuest : public guest_view::GuestView<WebViewGuest>,
                                              std::string* partition_name,
                                              bool* in_memory);
 
+  // Returns the webview partition ID associated with the render process
+  // represented by |render_process_host|, if any. Otherwise, an empty string is
+  // returned.
+  static std::string GetPartitionID(
+      const content::RenderProcessHost* render_process_host);
+
   static const char Type[];
 
   // Returns the stored rules registry ID of the given webview. Will generate