[vr] Close exit prompt when clicking on background

chrome/browser/android/vr_shell/ui_scene_manager.h

 // 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.
 
 #ifndef CHROME_BROWSER_ANDROID_VR_SHELL_UI_SCENE_MANAGER_H_
 #define CHROME_BROWSER_ANDROID_VR_SHELL_UI_SCENE_MANAGER_H_
 
 #include "base/gtest_prod_util.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
@@ skipping 36 matching lines @@
   void SetAudioCapturingIndicator(bool enabled);
 
   // These methods are currently stubbed.
   void SetHistoryButtonsEnabled(bool can_go_back, bool can_go_forward);
 
   void OnAppButtonClicked();
   void OnAppButtonGesturePerformed(UiInterface::Direction direction);
 
  private:
   FRIEND_TEST_ALL_PREFIXES(UiSceneManagerTest, UiUpdatesExitPrompt);
+  FRIEND_TEST_ALL_PREFIXES(UiSceneManagerTest, BackplaneClickClosesExitPrompt);
 
   void CreateScreenDimmer();
   void CreateSecurityWarnings();
   void CreateSystemIndicators();
   void CreateContentQuad();
   void CreateBackground();
   void CreateUrlBar();
   void CreateCloseButton();
 
   void ConfigureScene();
   void ConfigureSecurityWarnings();
   void UpdateBackgroundColor();
+  void CloseExitPrompt();
   void OnSecurityWarningTimer();
   void OnBackButtonClicked();
+  void OnBackplaneClicked();
   void OnSecurityIconClicked();
   void OnExitPromptPrimaryButtonClicked();
   void OnExitPromptSecondaryButtonClicked();
   void OnCloseButtonClicked();
   void OnUnsupportedMode(UiUnsupportedMode mode);
   int AllocateId();
   ColorScheme::Mode mode() const;
   const ColorScheme& color_scheme() const;
 
   VrBrowserInterface* browser_;
@@ skipping 33 matching lines @@
   base::OneShotTimer security_warning_timer_;
 
   base::WeakPtrFactory<UiSceneManager> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(UiSceneManager);
 };
 
 }  // namespace vr_shell
 
 #endif  // CHROME_BROWSER_ANDROID_VR_SHELL_UI_SCENE_MANAGER_H_