Close pop up notification when navigating to other site.

When BlockedPopupContainer stopped being a ConstrainedWindow, the
notification stopped being cleared in TabContents::MaybeCloseChildWindows.

http://crbug.com/8622
http://crbug.com/14150
TEST=See 8622 for repro steps.

Review URL: http://codereview.chromium.org/159287

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@21445 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/chrome/browser/tab_contents/tab_contents.cc b/chrome/browser/tab_contents/tab_contents.cc
index 3678335..a5eefc5d 100644
--- a/chrome/browser/tab_contents/tab_contents.cc
+++ b/chrome/browser/tab_contents/tab_contents.cc
@@ -1271,6 +1271,12 @@
     if (window)
       window->CloseConstrainedWindow();
   }
+
+  // Close the popup container.
+  if (blocked_popups_) {
+    blocked_popups_->Destroy();
+    blocked_popups_ = NULL;
+  }
 }
 
 void TabContents::UpdateStarredStateForCurrentURL() {