Allow exntesion resources to be loaded into DevTools front-end frame

chrome/browser/extensions/extension_protocols.cc

Index: chrome/browser/extensions/extension_protocols.cc
===================================================================
--- chrome/browser/extensions/extension_protocols.cc	(revision 55538)
+++ chrome/browser/extensions/extension_protocols.cc	(working copy)
@@ -79,9 +79,12 @@
 
   // Don't allow extension resources to be loaded from origins which are not
   // present in the extension's effective host permissions with the exception
-  // of empty origins and extension schemes.
+  // of empty origins, extension schemes and DevTools front-end.
+  GURL origin_url = GURL(info->frame_origin());
   if (!info->frame_origin().empty() &&
-      !GURL(info->frame_origin()).SchemeIs(chrome::kExtensionScheme)) {
+      !origin_url.SchemeIs(chrome::kExtensionScheme) &&
+      !(origin_url.SchemeIs(chrome::kChromeUIScheme) &&
+        origin_url.host() == chrome::kChromeUIDevToolsHost)) {
     ExtensionExtent host_permissions =
       context->GetEffectiveHostPermissionsForExtension(request->url().host());
     if (!host_permissions.ContainsURL(GURL(info->frame_origin())))