Prevent duplicate content script injection defined in manifest.json

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 <utility>
 #include <vector>
 
 #include "base/values.h"
@@ skipping 76 matching lines @@
   DCHECK_EQ(injection_host->id().type(), HostID::EXTENSIONS);
 
   return injection_host->CanExecuteOnFrame(
       effective_document_url,
       content::RenderFrame::FromWebFrame(frame),
       tab_id,
       true /* is_declarative */);
 }
 
 std::vector<blink::WebScriptSource> ProgrammaticScriptInjector::GetJsSources(
-    UserScript::RunLocation run_location) const {
+    UserScript::RunLocation run_location,
+    ScriptsRunInfo* scripts_run_info) const {
   DCHECK_EQ(GetRunLocation(), run_location);
   DCHECK(params_->is_javascript);
 
   return std::vector<blink::WebScriptSource>(
       1,
       blink::WebScriptSource(
           blink::WebString::fromUTF8(params_->code), params_->file_url));
 }
 
 std::vector<std::string> ProgrammaticScriptInjector::GetCssSources(
-    UserScript::RunLocation run_location) const {
+    UserScript::RunLocation run_location,
+    ScriptsRunInfo* scripts_run_info) const {
   DCHECK_EQ(GetRunLocation(), run_location);
   DCHECK(!params_->is_javascript);
 
   return std::vector<std::string>(1, params_->code);
 }
 
 void ProgrammaticScriptInjector::GetRunInfo(
     ScriptsRunInfo* scripts_run_info,
     UserScript::RunLocation run_location) const {
 }
@@ skipping 57 matching lines @@
   // frame deletions so nothing is left hanging).
   if (render_frame) {
     render_frame->Send(
         new ExtensionHostMsg_ExecuteCodeFinished(
             render_frame->GetRoutingID(), params_->request_id,
             error, url_, results_));
   }
 }
 
 }  // namespace extensions