Fixes leak of NativeTextfieldWin. The underlying HWND was getting

ui/views/controls/textfield/native_textfield_win.h

Index: ui/views/controls/textfield/native_textfield_win.h
diff --git a/ui/views/controls/textfield/native_textfield_win.h b/ui/views/controls/textfield/native_textfield_win.h
index eca2358cd9e9b117c49daffb9a0ff63fcab53c03..f9b8f268b56b3bec516feea334c4e5acfd709a01 100644
--- a/ui/views/controls/textfield/native_textfield_win.h
+++ b/ui/views/controls/textfield/native_textfield_win.h
@@ -219,6 +219,9 @@ class NativeTextfieldWin
   void OnKillFocus(HWND hwnd);
   void OnSysChar(TCHAR ch, UINT repeat_count, UINT flags);
 
+  // CWindowImpl overrides:
+  virtual void OnFinalMessage(HWND hwnd) OVERRIDE;
+
   // Helper function for OnChar() and OnKeyDown() that handles keystrokes that
   // could change the text in the edit.
   // Note: This function assumes GetCurrentMessage() returns a MSG with