Add UMA to track permission changes from the content settings menu

chrome/browser/content_settings/web_site_settings_uma_util.cc

Index: chrome/browser/content_settings/web_site_settings_uma_util.cc
diff --git a/chrome/browser/content_settings/web_site_settings_uma_util.cc b/chrome/browser/content_settings/web_site_settings_uma_util.cc
new file mode 100644
index 0000000000000000000000000000000000000000..4aa979d2dd26c547efba9b092e8dd94b83fb2b48
--- /dev/null
+++ b/chrome/browser/content_settings/web_site_settings_uma_util.cc
@@ -0,0 +1,34 @@
+// 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.
+
+#include "chrome/browser/content_settings/web_site_settings_uma_util.h"
+
+#include "base/metrics/histogram_macros.h"
+
+void WebSiteSettingsUmaUtil::LogPermissionChange(ContentSettingsType type,
+                                                 ContentSetting setting) {
+  ContentSettingsTypeHistogram histogram_value =
+      ContentSettingTypeToHistogramValue(type);
+  DCHECK_NE(histogram_value, CONTENT_SETTINGS_TYPE_HISTOGRAM_INVALID);
+  UMA_HISTOGRAM_ENUMERATION("WebsiteSettings.Menu.PermissionChanged",
+                            histogram_value,
+                            CONTENT_SETTINGS_HISTOGRAM_NUM_TYPES);
+
+  if (setting == ContentSetting::CONTENT_SETTING_ALLOW) {
+    UMA_HISTOGRAM_ENUMERATION("WebsiteSettings.Menu.PermissionChanged.Allowed",
+                              histogram_value,
+                              CONTENT_SETTINGS_HISTOGRAM_NUM_TYPES);
+  } else if (setting == ContentSetting::CONTENT_SETTING_BLOCK) {
+    UMA_HISTOGRAM_ENUMERATION("WebsiteSettings.Menu.PermissionChanged.Blocked",
+                              histogram_value,
+                              CONTENT_SETTINGS_HISTOGRAM_NUM_TYPES);
+  } else if (setting == ContentSetting::CONTENT_SETTING_DEFAULT) {
+    UMA_HISTOGRAM_ENUMERATION("WebsiteSettings.Menu.PermissionChanged.Reset",
+                              histogram_value,
+                              CONTENT_SETTINGS_HISTOGRAM_NUM_TYPES);
+  } else {
+    NOTREACHED() << "Requested to log permission change " << type << " to "
+                 << setting;
+  }
+}