MessageBubble which does not require separate window and does not grab input on mouse press event.

chrome/browser/views/info_bubble.cc

 // Copyright (c) 2010 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/views/info_bubble.h"
 
 #include "base/keyboard_codes.h"
 #include "chrome/browser/window_sizer.h"
 #include "chrome/common/notification_service.h"
 #include "gfx/canvas.h"
@@ skipping 231 matching lines @@
                              BubbleBorder::ArrowLocation arrow_location,
                              views::View* contents,
                              InfoBubbleDelegate* delegate) {
   InfoBubble* window = new InfoBubble;
   window->Init(parent, position_relative_to, arrow_location,
                contents, delegate);
   return window;
 }
 
 void InfoBubble::Close() {
+  GetFocusManager()->UnregisterAccelerator(
+      views::Accelerator(base::VKEY_ESCAPE, false, false, false), this);
+
   if (fade_away_on_close_)
     FadeOut();
   else
     Close(false);
 }
 
 void InfoBubble::AnimationEnded(const Animation* animation) {
   if (static_cast<int>(animation_->GetCurrentValue()) == 0) {
     // When fading out we just need to close the bubble at the end
     Close(false);
@@ skipping 29 matching lines @@
       WidgetGtk(TYPE_WINDOW),
       border_contents_(NULL),
 #elif defined(OS_WIN)
       border_(NULL),
 #endif
       delegate_(NULL),
       closed_(false),
       fade_away_on_close_(false) {
 }
 
+#if defined(OS_CHROMEOS)
+InfoBubble::InfoBubble(views::WidgetGtk::Type type)
+    : WidgetGtk(type),
+      border_contents_(NULL),
+      delegate_(NULL),
+      closed_(false),
+      fade_away_on_close_(false) {
+}
+#endif
+
 void InfoBubble::Init(views::Widget* parent,
                       const gfx::Rect& position_relative_to,
                       BubbleBorder::ArrowLocation arrow_location,
                       views::View* contents,
                       InfoBubbleDelegate* delegate) {
   delegate_ = delegate;
   position_relative_to_ = position_relative_to;
   arrow_location_ = arrow_location;
   contents_ = contents;
 
@@ skipping 190 matching lines @@
     animation_->Hide();
 }
 
 bool InfoBubble::AcceleratorPressed(const views::Accelerator& accelerator) {
   if (!delegate_ || delegate_->CloseOnEscape()) {
     Close(true);
     return true;
   }
   return false;
 }