Do not set the mouse event handler if Widget::SetCapture() fails

ui/views/widget/desktop_aura/desktop_window_tree_host_x11.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 "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
 
 #include <X11/extensions/shape.h>
 #include <X11/extensions/XInput2.h>
 #include <X11/Xatom.h>
 #include <X11/Xregion.h>
@@ skipping 1283 matching lines @@
 void DesktopWindowTreeHostX11::SetUseNativeFrame(bool use_native_frame) {
   use_native_frame_ = use_native_frame;
   ui::SetUseOSWindowFrame(xwindow_, use_native_frame);
   ResetWindowRegion();
 }
 
 void DesktopWindowTreeHostX11::OnCaptureReleased() {
   x11_capture_.reset();
   g_current_capture = NULL;
   OnHostLostWindowCapture();
-  native_widget_delegate_->OnMouseCaptureLost();
 }
 
 void DesktopWindowTreeHostX11::DispatchMouseEvent(ui::MouseEvent* event) {
   // In Windows, the native events sent to chrome are separated into client
   // and non-client versions of events, which we record on our LocatedEvent
   // structures. On X11, we emulate the concept of non-client. Before we pass
   // this event to the cross platform event handling framework, we need to
   // make sure it is appropriately marked as non-client if it's in the non
   // client area, or otherwise, we can get into a state where the a window is
   // set as the |mouse_pressed_handler_| in window_event_dispatcher.cc
@@ skipping 506 matching lines @@
   if (linux_ui) {
     ui::NativeTheme* native_theme = linux_ui->GetNativeTheme(window);
     if (native_theme)
       return native_theme;
   }
 
   return ui::NativeTheme::instance();
 }
 
 }  // namespace views