Pass result of blockage across content API when new tab blocked.

chrome/browser/ui/browser_tabstrip.h

Index: chrome/browser/ui/browser_tabstrip.h
===================================================================
--- chrome/browser/ui/browser_tabstrip.h	(revision 154977)
+++ chrome/browser/ui/browser_tabstrip.h	(working copy)
@@ -55,13 +55,15 @@
 // Creates a new tab with the already-created WebContents 'new_contents'.
 // The window for the added contents will be reparented correctly when this
 // method returns.  If |disposition| is NEW_POPUP, |pos| should hold the
-// initial position.
+// initial position. If |was_blocked| is non-NULL, then |*was_blocked| will be
+// set to true if the popup gets blocked, and left unchanged otherwise.
 void AddWebContents(Browser* browser,
                     content::WebContents* source_contents,
                     content::WebContents* new_contents,
                     WindowOpenDisposition disposition,
                     const gfx::Rect& initial_pos,
-                    bool user_gesture);
+                    bool user_gesture,
+                    bool* was__blocked);
 void CloseWebContents(Browser* browser, content::WebContents* contents);
 
 void CloseAllTabs(Browser* browser);