views: Extract Widget observer into its own header file.

chrome/browser/ui/views/chrome_to_mobile_bubble_view.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/views/chrome_to_mobile_bubble_view.h"
 
 #include "base/bind.h"
 #include "base/file_util.h"
 #include "base/message_loop.h"
 #include "base/string16.h"
@@ skipping 13 matching lines @@
 #include "ui/base/text/bytes_formatting.h"
 #include "ui/views/controls/button/checkbox.h"
 #include "ui/views/controls/button/radio_button.h"
 #include "ui/views/controls/button/text_button.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/label.h"
 #include "ui/views/controls/link.h"
 #include "ui/views/events/event.h"
 #include "ui/views/layout/grid_layout.h"
 #include "ui/views/layout/layout_constants.h"
+#include "ui/views/widget/widget.h"
 
 using views::GridLayout;
 
 namespace {
 
 // The title label's color; matches the bookmark bubble's title.
 const SkColor kTitleColor = 0xFF062D75;
 
 // The millisecond duration of the "Sending..." progress throb animation.
 const size_t kProgressThrobDurationMS = 2400;
@@ skipping 331 matching lines @@
   }
 
   // Update the view's contents to show the "Sending..." progress animation.
   cancel_->SetEnabled(false);
   send_->SetEnabled(false);
   send_->set_alignment(views::TextButtonBase::ALIGN_LEFT);
   progress_animation_.reset(new ui::ThrobAnimation(this));
   progress_animation_->SetDuration(kProgressThrobDurationMS);
   progress_animation_->StartThrobbing(-1);
 }