Implement permission embargo suppression metrics.

chrome/browser/permissions/permission_util.h

 // Copyright 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_PERMISSIONS_PERMISSION_UTIL_H_
 #define CHROME_BROWSER_PERMISSIONS_PERMISSION_UTIL_H_
 
 #include <string>
 
 #include "base/macros.h"
@@ skipping 17 matching lines @@
   DISMISSED = 2,
   IGNORED = 3,
   REVOKED = 4,
   REENABLED = 5,
   REQUESTED = 6,
 
   // Always keep this at the end.
   PERMISSION_ACTION_NUM,
 };
 
+// Identifies the source or reason for a permission status being returned. This
+// enum backs an UMA histogram and must be treated as append-only.
+enum class PermissionStatusSource {
+  // The reason for the status is not specified.
+  UNSPECIFIED,
+
+  // The status is the result of being blocked due to the user dismissing a
+  // permission prompt multiple times.
+  MULTIPLE_DISMISSALS,
+
+  // The status is the result of being blocked because the permission is on the
+  // safe browsing blacklist.
+  SAFE_BROWSING_BLACKLIST,
+
+  // The status is the result of being blocked by the permissions kill switch.
+  KILL_SWITCH,
+
+  // Must be kept last.
+  NUM

[raymes, 2017/02/22 23:13:50]

nit: I don't think this is needed anymore.

[dominickn, 2017/02/22 23:38:55]

Done.

+};
+
+struct PermissionResult {
+  PermissionResult(ContentSetting content_setting,
+                   PermissionStatusSource source);
+  ~PermissionResult();
+
+  ContentSetting content_setting;
+  PermissionStatusSource source;
+};

[raymes, 2017/02/22 23:13:50]

I think it would be good to move these into their own permission_result.h file
at some point (PermissionResult and PermissionStatusSource). Doesn't have to be
in this CL though.

[dominickn, 2017/02/22 23:38:54]

Acknowledged.

+
+struct PermissionTypeHash {
+  std::size_t operator()(const content::PermissionType& type) const;
+};

[raymes, 2017/02/22 23:13:50]

Is this needed?

[dominickn, 2017/02/22 23:38:55]

Odd, looks like whatever used it has been removed. Must have been timloh's
refactoring.

+
 // A utility class for permissions.
 class PermissionUtil {
  public:
   // Returns the permission string for the given permission.
   static std::string GetPermissionString(ContentSettingsType);
   // TODO(timloh): Remove this content::PermissionType overload when we add MIDI
   // to ContentSettingsType.
   static std::string GetPermissionString(content::PermissionType);
 
   // Return the stringified version of the ContentSettingsType enum that
@@ skipping 44 matching lines @@
     ContentSettingsType content_type_;
     PermissionSourceUI source_ui_;
     bool is_initially_allowed_;
   };
 
  private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PermissionUtil);
 };
 
 #endif  // CHROME_BROWSER_PERMISSIONS_PERMISSION_UTIL_H_