Add a feature which, when enabled, blocks permissions after X prompt dismissals.

chrome/browser/permissions/permission_decision_auto_blocker.h

Index: chrome/browser/permissions/permission_decision_auto_blocker.h
diff --git a/chrome/browser/permissions/permission_decision_auto_blocker.h b/chrome/browser/permissions/permission_decision_auto_blocker.h
new file mode 100644
index 0000000000000000000000000000000000000000..2b02f5fe7b4d55d40186cf5604fe0ae046e46489
--- /dev/null
+++ b/chrome/browser/permissions/permission_decision_auto_blocker.h
@@ -0,0 +1,49 @@
+// 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_PERMISSIONS_PERMISSION_DECISION_AUTO_BLOCKER_H_
+#define CHROME_BROWSER_PERMISSIONS_PERMISSION_DECISION_AUTO_BLOCKER_H_
+
+#include "base/callback_forward.h"
+#include "base/macros.h"
+#include "content/public/browser/permission_type.h"
+#include "url/gurl.h"
+
+class GURL;
+class Profile;
+
+class PermissionDecisionAutoBlocker {
+ public:
+  static void RemoveCountsByUrl(Profile* profile,
+                                base::Callback<bool(const GURL& url)> filter);
+
+  PermissionDecisionAutoBlocker();
+  bool ShouldChangeDismissalToBlock(Profile* profile,
+                                    const GURL& url,
+                                    content::PermissionType permission);
+
+ private:
+  friend class PermissionContextBaseTests;
+  friend class PermissionDecisionAutoBlockerUnitTest;
+
+  static const char kPromptDismissCountKey[];
+
+  // Returns the current number of dismissals for |permission| type at |url|.
+  // Exposed for testing.
+  int GetDismissalCount(Profile* profile,
+                        const GURL& url,
+                        content::PermissionType permission);
+
+  // Records that the user dismissed a permission prompt for type |permission|
+  // on |url| to a website setting. Returns the updated number of dismissals.
+  int RecordDismissalCount(Profile* profile,
+                           const GURL& url,
+                           content::PermissionType permission);
+
+  void UpdateFromVariations();
+
+  int prompt_dismissals_before_block_;
+};
+
+#endif  // CHROME_BROWSER_PERMISSIONS_PERMISSION_DECISION_AUTO_BLOCKER_H_