Improve error message for failing code insertion on about:-URLs

extensions/renderer/programmatic_script_injector.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "extensions/renderer/programmatic_script_injector.h"
 
 #include <vector>
 
 #include "base/values.h"
+#include "content/public/common/url_constants.h"
 #include "content/public/renderer/render_view.h"
 #include "extensions/common/error_utils.h"
 #include "extensions/common/extension_messages.h"
 #include "extensions/common/manifest_constants.h"
 #include "extensions/common/permissions/permissions_data.h"
 #include "extensions/renderer/injection_host.h"
 #include "extensions/renderer/script_context.h"
 #include "third_party/WebKit/public/platform/WebString.h"
 #include "third_party/WebKit/public/web/WebDocument.h"
 #include "third_party/WebKit/public/web/WebFrame.h"
@@ skipping 91 matching lines @@
     ScriptsRunInfo* scripts_run_info,
     UserScript::RunLocation run_location) {
   results_ = execution_results.Pass();
   Finish(std::string());
 }
 
 void ProgrammaticScriptInjector::OnWillNotInject(InjectFailureReason reason) {
   std::string error;
   switch (reason) {
     case NOT_ALLOWED:
-      error = ErrorUtils::FormatErrorMessage(manifest_errors::kCannotAccessPage,
-                                             url_.spec());
+      if (url_.SchemeIs(url::kAboutScheme)) {
+        error = ErrorUtils::FormatErrorMessage(
+            manifest_errors::kCannotAccessAboutUrl, url_.spec());
+      } else {
+        error = ErrorUtils::FormatErrorMessage(
+            manifest_errors::kCannotAccessPage, url_.spec());
+      }
       break;
     case EXTENSION_REMOVED:  // no special error here.
     case WONT_INJECT:
       break;
   }
   Finish(error);
 }
 
 UserScript::RunLocation ProgrammaticScriptInjector::GetRunLocation() const {
   return static_cast<UserScript::RunLocation>(params_->run_at);
 }
 
 void ProgrammaticScriptInjector::Finish(const std::string& error) {
   DCHECK(!finished_);
   finished_ = true;
 
   render_view_->Send(new ExtensionHostMsg_ExecuteCodeFinished(
       render_view_->GetRoutingID(),
       params_->request_id,
       error,
       url_,
       *results_));
 }
 
 }  // namespace extensions