Attempt at fixing possible shutdown crash

chrome/browser/ui/views/frame/desktop_browser_frame_aura.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/frame/desktop_browser_frame_aura.h"
 
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/ui/views/frame/browser_desktop_root_window_host.h"
+#include "chrome/browser/ui/views/frame/browser_shutdown.h"
 #include "chrome/browser/ui/views/frame/browser_view.h"
 #include "chrome/browser/ui/views/frame/desktop_user_action_handler_aura.h"
 #include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "ui/aura/client/aura_constants.h"
 #include "ui/aura/root_window.h"
 #include "ui/aura/window.h"
 #include "ui/aura/window_observer.h"
 #include "ui/base/hit_test.h"
 #include "ui/base/l10n/l10n_util.h"
@@ skipping 20 matching lines @@
 ///////////////////////////////////////////////////////////////////////////////
 // DesktopBrowserFrameAura, protected:
 
 DesktopBrowserFrameAura::~DesktopBrowserFrameAura() {
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 // DesktopBrowserFrameAura, views::DesktopNativeWidgetAura overrides:
 
 void DesktopBrowserFrameAura::OnHostClosed() {
+  // Destroy any remaining WebContents early on. Doing so may result in
+  // calling back to one of the Views/LayoutManagers or supporting classes of
+  // BrowserView. By destroying here we ensure all said classes are valid.
+  DestroyBrowserWebContents(browser_view_->browser());
   aura::client::SetVisibilityClient(GetNativeView()->GetRootWindow(), NULL);
   DesktopNativeWidgetAura::OnHostClosed();
 }
 
 void DesktopBrowserFrameAura::InitNativeWidget(
     const views::Widget::InitParams& params) {
   browser_desktop_root_window_host_ =
       BrowserDesktopWindowTreeHost::CreateBrowserDesktopWindowTreeHost(
           browser_frame_,
           this,
@@ skipping 27 matching lines @@
   return this;
 }
 
 bool DesktopBrowserFrameAura::UsesNativeSystemMenu() const {
   return browser_desktop_root_window_host_->UsesNativeSystemMenu();
 }
 
 int DesktopBrowserFrameAura::GetMinimizeButtonOffset() const {
   return browser_desktop_root_window_host_->GetMinimizeButtonOffset();
 }