Remove use of deprecated MessageLoop methods in chrome/.

chrome/browser/ui/views/new_back_shortcut_bubble.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 "chrome/browser/ui/views/new_back_shortcut_bubble.h"
 
 #include <utility>
 
-#include "base/message_loop/message_loop.h"
+#include "base/location.h"
+#include "base/single_thread_task_runner.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "chrome/browser/ui/views/exclusive_access_bubble_views_context.h"
 #include "chrome/browser/ui/views/subtle_notification_view.h"
 #include "chrome/grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/animation/animation.h"
 #include "ui/gfx/animation/slide_animation.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/strings/grit/ui_strings.h"
 #include "ui/views/border.h"
@@ skipping 19 matching lines @@
           bubble_view_context_->GetBubbleParentView(),
           view_,
           false)) {
   UpdateContent(forward);
 }
 
 NewBackShortcutBubble::~NewBackShortcutBubble() {
   // We might need to delete the widget asynchronously. See rationale in
   // ~ExclusiveAccessBubbleViews.
   popup_->Close();
-  base::MessageLoop::current()->DeleteSoon(FROM_HERE, popup_);
+  base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, popup_);
 }
 
 void NewBackShortcutBubble::UpdateContent(bool forward) {
   // Note: The key names are parameters so that we can vary by operating system
   // or change the direction of the arrow as necessary (see
   // https://crbug.com/612685).
 
 #if defined(OS_MACOSX)
   // U+2318 = PLACE OF INTEREST SIGN (Mac Command symbol).
   base::string16 accelerator = base::WideToUTF16(L"\x2318");
@@ skipping 48 matching lines @@
   int desired_top = kPopupTopPx - view_->border()->GetInsets().top();
   int y = widget_bounds.y() + desired_top;
   return gfx::Rect(gfx::Point(x, y), size);
 }
 
 void NewBackShortcutBubble::OnTimerElapsed() {
   // Hide the bubble.
   animation_->SetSlideDuration(kSlideOutDurationMs);
   animation_->Hide();
 }