Extract executeScript-like functionality into a single ExtensionScriptExecutor class.

chrome/browser/extensions/api/offscreen_tabs/offscreen_tabs_api.cc

 // Copyright (c) 2012 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 "chrome/browser/extensions/api/offscreen_tabs/offscreen_tabs_api.h"
 
 #include <algorithm>
 #include <vector>
 
 #include "base/hash_tables.h"
@@ skipping 781 matching lines @@
   EXTENSION_FUNCTION_VALIDATE(args_->GetInteger(0, &offscreen_tab_id));
 
   OffscreenTab* offscreen_tab = NULL;
   if (!GetMap()->GetOffscreenTab(
           offscreen_tab_id, this, &offscreen_tab, &error_))
     return false;
 
   DictionaryValue* update_props;
   EXTENSION_FUNCTION_VALIDATE(args_->GetDictionary(1, &update_props));
 
-  web_contents_ = offscreen_tab->web_contents();
+  tab_contents_ = offscreen_tab->tab_contents();
   bool is_async = false;
   if (!UpdateURLIfPresent(update_props, &is_async))
     return false;
 
   // Update the width and height, if specified.
   if (update_props->HasKey(tabs_keys::kWidthKey) ||
       update_props->HasKey(tabs_keys::kHeightKey)) {
+    const gfx::Size& size =
+        tab_contents_->web_contents()->GetView()->GetContainerSize();
+
     int width;
     if (update_props->HasKey(tabs_keys::kWidthKey))
       EXTENSION_FUNCTION_VALIDATE(
           update_props->GetInteger(tabs_keys::kWidthKey, &width));
     else
-      web_contents_->GetView()->GetContainerSize().width();
+      width = size.width();

[koz (OOO until 15th September), 2012/05/11 01:09:16]

Good spot!

 
     int height;
     if (update_props->HasKey(tabs_keys::kHeightKey))
       EXTENSION_FUNCTION_VALIDATE(
           update_props->GetInteger(tabs_keys::kHeightKey, &height));
     else
-      web_contents_->GetView()->GetContainerSize().height();
+      height = size.height();
 
     offscreen_tab->SetSize(width, height);
   }
 
   // The response is sent from UpdateTabFunction::OnExecuteCodeFinish in the
   // async case (when a "javascript": URL is sent to a tab).
   if (!is_async)
     SendResponse(true);
 
   return true;
 }
 
 void UpdateOffscreenTabFunction::PopulateResult() {
   // There's no result associated with this callback.
 }