Remove references to DOMUIContents. It looks like the class doesn't exist.

chrome/browser/tab_contents/tab_contents.h

Index: chrome/browser/tab_contents/tab_contents.h
diff --git a/chrome/browser/tab_contents/tab_contents.h b/chrome/browser/tab_contents/tab_contents.h
index 7fb4822e16197e27a1e006428c0efc09b12e030c..f892775154652471fb9e0728df03f80c475d2f70 100644
--- a/chrome/browser/tab_contents/tab_contents.h
+++ b/chrome/browser/tab_contents/tab_contents.h
@@ -72,7 +72,6 @@ class Message;
 class AutofillManager;
 class BlockedPopupContainer;
 class DOMUI;
-class DOMUIContents;
 class DownloadItem;
 class LoadNotificationDetails;
 class OmniboxSearchHint;
@@ -135,9 +134,6 @@ class TabContents : public PageNavigator,
   const PropertyBag* property_bag() const { return &property_bag_; }
   PropertyBag* property_bag() { return &property_bag_; }
 
-  // Returns this object as a DOMUIContents if it is one, and NULL otherwise.
-  virtual DOMUIContents* AsDOMUIContents() { return NULL; }
-
   TabContentsDelegate* delegate() const { return delegate_; }
   void set_delegate(TabContentsDelegate* d) { delegate_ = d; }