views: Add a new ctor to MessageBoxView that takes only a InitParams.

ui/views/controls/message_box_view.h

Index: ui/views/controls/message_box_view.h
diff --git a/ui/views/controls/message_box_view.h b/ui/views/controls/message_box_view.h
index 7325a05b0675210ce0e428d585ce76a0f7b7d653..77cff311f0f4039b0727e25f2e7305e41b337286 100644
--- a/ui/views/controls/message_box_view.h
+++ b/ui/views/controls/message_box_view.h
@@ -37,14 +37,16 @@ class VIEWS_EXPORT MessageBoxView : public View {
     HAS_PROMPT_FIELD = 1 << 1,
   };
 
+  MessageBoxView(const string16& message);

[sky, 2012/05/10 15:38:53]

Is there really a compelling reason to do this? I would prefer a single
constructor.

[tfarina, 2012/05/10 15:42:36]

No. Besides the cleanness in the caller side. But if you don't want this, OK!

+
   MessageBoxView(int options,
                  const string16& message,
-                 const string16& default_prompt,
-                 int message_width);
+                 const string16& default_prompt);
 
   MessageBoxView(int options,
                  const string16& message,
-                 const string16& default_prompt);
+                 const string16& default_prompt,
+                 int message_width);
 
   virtual ~MessageBoxView();