Create a content::ResourceContext.

chrome/test/testing_profile.h

Index: chrome/test/testing_profile.h
diff --git a/chrome/test/testing_profile.h b/chrome/test/testing_profile.h
index 154294f2691c54cd50080a69df0a12e5bd1485f6..0a9ec468f83e3069e7d8537f206e3681ca37a636 100644
--- a/chrome/test/testing_profile.h
+++ b/chrome/test/testing_profile.h
@@ -12,6 +12,10 @@
 #include "base/timer.h"
 #include "chrome/browser/profiles/profile.h"
 
+namespace content {
+class ResourceContextGetter;
+}
+
 namespace history {
 class TopSites;
 }
@@ -210,6 +214,8 @@ class TestingProfile : public Profile {
   virtual net::URLRequestContextGetter* GetRequestContextForIsolatedApp(
       const std::string& app_id);
 
+  virtual content::ResourceContextGetter* GetResourceContext();
+
   virtual net::SSLConfigService* GetSSLConfigService();
   virtual UserStyleSheetWatcher* GetUserStyleSheetWatcher();
   virtual FindBarState* GetFindBarState();