Add an experimental keyboard lock, where Esc must be held to exit.

chrome/browser/ui/exclusive_access/exclusive_access_manager.h

 // Copyright (c) 2015 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_UI_EXCLUSIVE_ACCESS_EXCLUSIVE_ACCESS_MANAGER_H_
 #define CHROME_BROWSER_UI_EXCLUSIVE_ACCESS_EXCLUSIVE_ACCESS_MANAGER_H_
 
 #include "base/feature_list.h"
 #include "base/macros.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/timer/timer.h"
 #include "chrome/browser/ui/exclusive_access/exclusive_access_bubble_type.h"
 #include "chrome/browser/ui/exclusive_access/fullscreen_controller.h"
 #include "chrome/browser/ui/exclusive_access/mouse_lock_controller.h"
 
 class ExclusiveAccessContext;
 class FullscreenController;
 class GURL;
 class MouseLockController;
 
 namespace content {
@@ skipping 18 matching lines @@
     return &mouse_lock_controller_;
   }
 
   ExclusiveAccessContext* context() const { return exclusive_access_context_; }
 
   ExclusiveAccessBubbleType GetExclusiveAccessExitBubbleType() const;
   void UpdateExclusiveAccessExitBubbleContent();
 
   GURL GetExclusiveAccessBubbleURL() const;
 
+  static bool IsExperimentalKeyboardLockUIEnabled();
   static bool IsSimplifiedFullscreenUIEnabled();
 
   // Callbacks ////////////////////////////////////////////////////////////////
 
   // Called by Browser::TabDeactivated.
   void OnTabDeactivated(content::WebContents* web_contents);
 
   // Called by Browser::ActiveTabChanged.
   void OnTabDetachedFromView(content::WebContents* web_contents);
 
   // Called by Browser::TabClosingAt.
   void OnTabClosing(content::WebContents* web_contents);
 
   // Called by Browser::PreHandleKeyboardEvent.
   bool HandleUserKeyPress(const content::NativeWebKeyboardEvent& event);
 
   // Called by Browser::ContentsMouseEvent.
   void OnUserInput();
 
   // Called by platform ExclusiveAccessExitBubble.
   void OnAcceptExclusiveAccessPermission();
   void OnDenyExclusiveAccessPermission();
   void ExitExclusiveAccess();
   void RecordBubbleReshownUMA(ExclusiveAccessBubbleType type);
 
  private:
+  // Called when the user has held down Escape.
+  void HandleUserHeldEscape();
+
   ExclusiveAccessContext* const exclusive_access_context_;
   FullscreenController fullscreen_controller_;
   MouseLockController mouse_lock_controller_;
+  base::OneShotTimer hold_timer_;
 
   DISALLOW_COPY_AND_ASSIGN(ExclusiveAccessManager);
 };
 
 #endif  // CHROME_BROWSER_UI_EXCLUSIVE_ACCESS_EXCLUSIVE_ACCESS_MANAGER_H_