Do not show permission bubble when browser is not active

chrome/browser/permissions/permission_request_manager.h

Index: chrome/browser/permissions/permission_request_manager.h
diff --git a/chrome/browser/permissions/permission_request_manager.h b/chrome/browser/permissions/permission_request_manager.h
index b2df0b9d08a0a07172227246d1df40568b7ba35b..17862776ac1c37925a203894faf1dd74550c9ae2 100644
--- a/chrome/browser/permissions/permission_request_manager.h
+++ b/chrome/browser/permissions/permission_request_manager.h
@@ -102,6 +102,10 @@ class PermissionRequestManager
   void AddObserver(Observer* observer);
   void RemoveObserver(Observer* observer);
 
+  // Called when |web_contents()| is active, and its browser's visibility
+  // changed.
+  void OnBrowserVisibilityChanged(bool visible);
+
   // Do NOT use this methods in production code. Use this methods in browser
   // tests that need to accept or deny permissions when requested in
   // JavaScript. Your test needs to set this appropriately, and then the bubble
@@ -186,6 +190,9 @@ class PermissionRequestManager
   // The UI surface to be used to display the permissions requests.
   std::unique_ptr<PermissionPrompt> view_;
 
+  // Whether the browser that hosts |web_contents()| is visible.
+  bool browser_visible_;
+
   std::vector<PermissionRequest*> requests_;
   std::vector<PermissionRequest*> queued_requests_;
   std::vector<PermissionRequest*> queued_frame_requests_;