Switch Extensions::TabHelper to use WebContents, WebContentsUserData.

chrome/browser/extensions/api/tabs/tabs.cc

Index: chrome/browser/extensions/api/tabs/tabs.cc
diff --git a/chrome/browser/extensions/api/tabs/tabs.cc b/chrome/browser/extensions/api/tabs/tabs.cc
index 02ef4747f582e7e08a63e2bddb904d11ae5977fd..37755111b5a6d212a386e3e478ee3b8199a08ec5 100644
--- a/chrome/browser/extensions/api/tabs/tabs.cc
+++ b/chrome/browser/extensions/api/tabs/tabs.cc
@@ -615,8 +615,10 @@ bool CreateWindowFunction::RunImpl() {
   for (std::vector<GURL>::iterator i = urls.begin(); i != urls.end(); ++i) {
     TabContents* tab = chrome::AddSelectedTabWithURL(
         new_window, *i, content::PAGE_TRANSITION_LINK);
-    if (window_type == Browser::TYPE_PANEL)
-      tab->extension_tab_helper()->SetExtensionAppIconById(extension_id);
+    if (window_type == Browser::TYPE_PANEL) {
+      extensions::TabHelper::FromWebContents(tab->web_contents())->
+          SetExtensionAppIconById(extension_id);
+    }
   }
   if (contents) {
     TabStripModel* target_tab_strip = new_window->tab_strip_model();
@@ -1346,14 +1348,15 @@ bool UpdateTabFunction::UpdateURLIfPresent(DictionaryValue* update_props,
       return false;
     }
 
-    tab_contents_->extension_tab_helper()->script_executor()->ExecuteScript(
-        extension_id(),
-        ScriptExecutor::JAVASCRIPT,
-        url.path(),
-        ScriptExecutor::TOP_FRAME,
-        extensions::UserScript::DOCUMENT_IDLE,
-        ScriptExecutor::MAIN_WORLD,
-        base::Bind(&UpdateTabFunction::OnExecuteCodeFinished, this));
+    extensions::TabHelper::FromWebContents(tab_contents_->web_contents())->
+        script_executor()->ExecuteScript(
+            extension_id(),
+            ScriptExecutor::JAVASCRIPT,
+            url.path(),
+            ScriptExecutor::TOP_FRAME,
+            extensions::UserScript::DOCUMENT_IDLE,
+            ScriptExecutor::MAIN_WORLD,
+            base::Bind(&UpdateTabFunction::OnExecuteCodeFinished, this));
 
     *is_async = true;
     return true;