Fix nullptr dereference of ToolbarActionView

chrome/browser/ui/views/toolbar/browser_actions_container.cc

 // Copyright 2013 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/toolbar/browser_actions_container.h"
 
 #include <utility>
 
 #include "base/compiler_specific.h"
 #include "base/memory/ptr_util.h"
@@ skipping 150 matching lines @@
    ToolbarActionViewController* view_controller,
    size_t index) {
   ToolbarActionView* view = new ToolbarActionView(view_controller, this);
   toolbar_action_views_.insert(toolbar_action_views_.begin() + index,
                                base::WrapUnique(view));
   AddChildViewAt(view, index);
 }
 
 void BrowserActionsContainer::RemoveViewForAction(
     ToolbarActionViewController* action) {
+  std::unique_ptr<ToolbarActionView> view;
   for (ToolbarActionViews::iterator iter = toolbar_action_views_.begin();
        iter != toolbar_action_views_.end(); ++iter) {
     if ((*iter)->view_controller() == action) {
+      std::swap(view, *iter);
       toolbar_action_views_.erase(iter);
       break;
     }
   }
 }
 
 void BrowserActionsContainer::RemoveAllViews() {
   toolbar_action_views_.clear();
 }
 
@@ skipping 474 matching lines @@
   }
 }
 
 void BrowserActionsContainer::ClearActiveBubble(views::Widget* widget) {
   DCHECK(active_bubble_);
   DCHECK_EQ(active_bubble_->GetWidget(), widget);
   widget->RemoveObserver(this);
   active_bubble_ = nullptr;
   toolbar_actions_bar_->OnBubbleClosed();
 }