Fix bug in quicklaunch

mash/quick_launch/quick_launch_application.cc

 // Copyright 2016 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 "mash/quick_launch/quick_launch_application.h"
 
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "base/strings/string16.h"
 #include "base/strings/string_util.h"
@@ skipping 141 matching lines @@
   DISALLOW_COPY_AND_ASSIGN(QuickLaunchUI);
 };
 
 QuickLaunchApplication::QuickLaunchApplication() {}
 QuickLaunchApplication::~QuickLaunchApplication() {}
 
 void QuickLaunchApplication::RemoveWindow(views::Widget* window) {
   auto it = std::find(windows_.begin(), windows_.end(), window);
   DCHECK(it != windows_.end());
   windows_.erase(it);
-  if (windows_.empty())
+  if (windows_.empty() && base::MessageLoop::current()->is_running())
     base::MessageLoop::current()->QuitWhenIdle();
 }
 
 void QuickLaunchApplication::Initialize(shell::Connector* connector,
                                         const shell::Identity& identity,
                                         uint32_t id) {
   connector_ = connector;
   tracing_.Initialize(connector, identity.name());
 
   aura_init_.reset(new views::AuraInit(connector, "views_mus_resources.pak"));
@@ skipping 25 matching lines @@
   windows_.push_back(window);
 }
 
 void QuickLaunchApplication::Create(shell::Connection* connection,
                                     mojom::LaunchableRequest request) {
   bindings_.AddBinding(this, std::move(request));
 }
 
 }  // namespace quick_launch
 }  // namespace mash