Fix cancelling permission requests on Android when the PermissionRequestManager is enabled

chrome/browser/ui/permission_bubble/permission_prompt.h

 // Copyright 2014 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_PERMISSION_BUBBLE_PERMISSION_PROMPT_H_
 #define CHROME_BROWSER_UI_PERMISSION_BUBBLE_PERMISSION_PROMPT_H_
 
 #include <memory>
 #include <vector>
 
@@ skipping 30 matching lines @@
       Factory;
 
   // Create a platform specific instance.
   static std::unique_ptr<PermissionPrompt> Create(
       content::WebContents* web_contents);
   virtual ~PermissionPrompt() {}
 
   // Sets the delegate which will receive UI events forwarded from the prompt.
   virtual void SetDelegate(Delegate* delegate) = 0;
 
-  // Causes the request UI to show up with the given contents. This method may
-  // be called with mostly-identical contents to the existing contents. This can
-  // happen, for instance, if a new permission is requested and
-  // CanAcceptRequestUpdate() is true.
-  // Important: the view must not store any of the request objects it receives
-  // in this call.
+  // Causes the request UI to show up with the given contents. This is only
+  // called when !IsVisible(), except when called after MaybeCancelRequest().
   virtual void Show(const std::vector<PermissionRequest*>& requests,
                     const std::vector<bool>& accept_state) = 0;
 
-  // Returns true if the view can accept a new Show() command to coalesce
-  // requests. Currently the policy is that this should return true if the view
-  // is being shown and the mouse is not over the view area (!IsMouseHovered).
-  virtual bool CanAcceptRequestUpdate() = 0;
+  // Try to cancel (i.e. hide and don't run callbacks) the current request and
+  // return whether it was cancelled. Currently the policy is that this should
+  // fail if the view is being shown and the mouse is not over the view area
+  // (!IsMouseHovered). This invalidates request objects from the last Show()
+  // call, so if the cancel failed, Show() will be called with the cancelled
+  // requests replaced with dummy PermissionRequest objects.
+  virtual bool MaybeCancelRequest() = 0;
 
   // Returns true if the prompt UI will manage hiding itself when the user
   // resolves the prompt, on page navigation/destruction, and on tab switching.
   virtual bool HidesAutomatically() = 0;
 
   // Hides the permission prompt.
   virtual void Hide() = 0;
 
   // Returns true if there is a prompt currently showing.
   virtual bool IsVisible() = 0;
 
   // Updates where the prompt should be anchored. ex: fullscreen toggle.
   virtual void UpdateAnchorPosition() = 0;
 
   // Returns a reference to this prompt's native window.
   // TODO(hcarmona): Remove this as part of the bubble API work.
   virtual gfx::NativeWindow GetNativeWindow() = 0;
 };
 
 #endif  // CHROME_BROWSER_UI_PERMISSION_BUBBLE_PERMISSION_PROMPT_H_