[HBD] If DefaultPluginPolicy set to 3, prompt should allow flash for the next page load only

chrome/browser/plugins/flash_temporary_permission_tracker.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_PLUGINS_FLASH_TEMPORARY_PERMISSION_TRACKER_H_
+#define CHROME_BROWSER_PLUGINS_FLASH_TEMPORARY_PERMISSION_TRACKER_H_
+
+#include <map>
+
+#include "base/synchronization/lock.h"
+#include "components/keyed_service/core/refcounted_keyed_service.h"
+#include "url/gurl.h"
+
+class Profile;
+
+namespace content {
+class WebContents;
+}  // namespace content
+
+// This class tracks temporary permission grants to allow flash to run on web
+// pages. This is used when the enterprise plugins setting is set to ASK. After
+// permission has been given to use flash, the page is automatically refreshed
+// so we need to make sure we don't revoke access when the page is first
+// refreshed. But any subsequent navigations or destroying the render frame
+// should revoke access. This class is safe to use from any thread.
+class FlashTemporaryPermissionTracker : public RefcountedKeyedService {
+ public:
+  static scoped_refptr<FlashTemporaryPermissionTracker> Get(Profile* profile);
+
+  // Returns true if flash is enabled for a given |url|.
+  bool IsFlashEnabled(const GURL& url);
+
+  // Call if flash was enabled in the main frame of a given |web_contents|.
+  void FlashEnabledForWebContents(content::WebContents* web_contents);
+
+ private:
+  friend class FlashTemporaryPermissionTrackerFactory;
+  friend class FlashTemporaryPermissionTrackerTest;
+
+  class GrantObserver;
+
+  explicit FlashTemporaryPermissionTracker(Profile* profile);
+  ~FlashTemporaryPermissionTracker() override;
+
+  // Revoke access from the given origin.
+  void RevokeAccess(const GURL& origin);
+
+  // RefCountedProfileKeyedBase method override.
+  void ShutdownOnUIThread() override;
+
+  Profile* profile_;
+
+  // We use GURLs to store the origins because we need to support the file:
+  // scheme comparing equal to itself.
+  // TODO(raymes): Revisit this after we decide what to do with plugins on file:
+  // URLs.
+  std::map<GURL, std::unique_ptr<GrantObserver>> granted_origins_;
+
+  // Lock to protect |granted_origins_|. This is needed because IsFlashEnabled
+  // may be called from any thread via the ChromePluginServiceFilter.
+  base::Lock granted_origins_lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(FlashTemporaryPermissionTracker);
+};
+
+#endif  // CHROME_BROWSER_PLUGINS_FLASH_TEMPORARY_PERMISSION_TRACKER_H_