[Extensions] Isolate ExtensionFunction results_ and error_

extensions/browser/api/guest_view/web_view/web_view_internal_api.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/browser/api/guest_view/web_view/web_view_internal_api.h"
 
 #include <utility>
 
 #include "base/guid.h"
 #include "base/memory/ptr_util.h"
@@ skipping 497 matching lines @@
 
   if (!params->instance_id)
     return RespondNow(Error(kViewInstanceIdError));
 
   GURL owner_base_url(
       render_frame_host()->GetSiteInstance()->GetSiteURL().GetWithEmptyPath());
   content::WebContents* sender_web_contents = GetSenderWebContents();
   HostID host_id = GenerateHostIDFromEmbedder(extension(), sender_web_contents);
   bool incognito_enabled = browser_context()->IsOffTheRecord();
 
+  std::string error;
   std::unique_ptr<UserScriptList> result =
       ParseContentScripts(params->content_script_list, extension(), host_id,
-                          incognito_enabled, owner_base_url, &error_);
+                          incognito_enabled, owner_base_url, &error);
   if (!result)
-    return RespondNow(Error(error_));
+    return RespondNow(Error(error));
 
   WebViewContentScriptManager* manager =
       WebViewContentScriptManager::Get(browser_context());
   DCHECK(manager);
 
   manager->AddContentScripts(
       sender_web_contents->GetRenderProcessHost()->GetID(), render_frame_host(),
       params->instance_id, host_id, std::move(result));
 
   return RespondNow(NoArguments());
@@ skipping 242 matching lines @@
 WebViewInternalLoadDataWithBaseUrlFunction::Run() {
   std::unique_ptr<web_view_internal::LoadDataWithBaseUrl::Params> params(
       web_view_internal::LoadDataWithBaseUrl::Params::Create(*args_));
   EXTENSION_FUNCTION_VALIDATE(params.get());
 
   // If a virtual URL was provided, use it. Otherwise, the user will be shown
   // the data URL.
   std::string virtual_url =
       params->virtual_url ? *params->virtual_url : params->data_url;
 
+  std::string error;
   bool successful = guest_->LoadDataWithBaseURL(
-      params->data_url, params->base_url, virtual_url, &error_);
+      params->data_url, params->base_url, virtual_url, &error);
   if (successful)
     return RespondNow(NoArguments());
-  return RespondNow(Error(error_));
+  return RespondNow(Error(error));
 }
 
 WebViewInternalGoFunction::WebViewInternalGoFunction() {
 }
 
 WebViewInternalGoFunction::~WebViewInternalGoFunction() {
 }
 
 ExtensionFunction::ResponseAction WebViewInternalGoFunction::Run() {
   std::unique_ptr<web_view_internal::Go::Params> params(
@@ skipping 176 matching lines @@
   // Will finish asynchronously.
   return true;
 }
 
 void WebViewInternalClearDataFunction::ClearDataDone() {
   Release();  // Balanced in RunAsync().
   SendResponse(true);
 }
 
 }  // namespace extensions