Create CoreTabHelper, move remaining core TCW functionality into it.

chrome/browser/extensions/extension_tabs_module.cc

Index: chrome/browser/extensions/extension_tabs_module.cc
diff --git a/chrome/browser/extensions/extension_tabs_module.cc b/chrome/browser/extensions/extension_tabs_module.cc
index 71d3b83233ddd2b9e28e3c0de505a5170dbc1290..5141327f7831a4b9f224012505182953ac1931eb 100644
--- a/chrome/browser/extensions/extension_tabs_module.cc
+++ b/chrome/browser/extensions/extension_tabs_module.cc
@@ -31,6 +31,7 @@
 #include "chrome/browser/ui/browser_list.h"
 #include "chrome/browser/ui/browser_navigator.h"
 #include "chrome/browser/ui/browser_window.h"
+#include "chrome/browser/ui/tab_contents/core_tab_helper.h"
 #include "chrome/browser/ui/tab_contents/tab_contents_wrapper.h"
 #include "chrome/browser/ui/window_sizer.h"
 #include "chrome/browser/web_applications/web_app.h"
@@ -1447,7 +1448,7 @@ bool CaptureVisibleTabFunction::RunImpl() {
 
   // Ask the renderer for a snapshot of the tab.
   TabContentsWrapper* wrapper = browser->GetSelectedTabContentsWrapper();
-  wrapper->CaptureSnapshot();
+  wrapper->core_tab_helper()->CaptureSnapshot();
   registrar_.Add(this,
                  chrome::NOTIFICATION_TAB_SNAPSHOT_TAKEN,
                  content::Source<TabContentsWrapper>(wrapper));