Remove DO_NOT_USE from CONTENT_SETTINGS_NUM_TYPES_DO_NOT_USE

We were originally planning to make content settings type a string, but
that effort was never completed. This comment is just adding confusion
at the moment.

Review-Url: https://codereview.chromium.org/2965183002
Cr-Commit-Position: refs/heads/master@{#485432}

chrome/common/common_param_traits_macros.h

@@ -11,7 +11,6 @@
 #include "components/content_settings/core/common/content_settings_types.h"
 #include "ipc/ipc_message_macros.h"
 
-IPC_ENUM_TRAITS_MAX_VALUE(ContentSettingsType,
-                          CONTENT_SETTINGS_NUM_TYPES_DO_NOT_USE - 1)
+IPC_ENUM_TRAITS_MAX_VALUE(ContentSettingsType, CONTENT_SETTINGS_NUM_TYPES - 1)
 
 #endif  // CHROME_COMMON_COMMON_PARAM_TRAITS_MACROS_H_

components/content_settings/core/common/content_settings.cc

@@ -80,7 +80,7 @@ int ContentSettingTypeToHistogramValue(ContentSettingsType content_setting,
                           return a.type < b.type;
                         }));
   static_assert(kHistogramValue[kNumHistogramValues - 1].type ==
-                    CONTENT_SETTINGS_NUM_TYPES_DO_NOT_USE - 1,
+                    CONTENT_SETTINGS_NUM_TYPES - 1,
                 "Update content settings histogram lookup");
 
   const HistogramValue* found = std::lower_bound(

components/content_settings/core/common/content_settings_types.h

@@ -71,8 +71,7 @@ enum ContentSettingsType {
   // specific origin.
   CONTENT_SETTINGS_TYPE_MEDIA_ENGAGEMENT,
 
-  // WARNING: This enum is going to be removed soon. Do not depend on NUM_TYPES.
-  CONTENT_SETTINGS_NUM_TYPES_DO_NOT_USE,
+  CONTENT_SETTINGS_NUM_TYPES,
 };
 
 struct ContentSettingsTypeHash {