Fix incorrect IPC_ENUM_TRAITS_MAX_VALUE for NTPLoggingEventType

The comment for IPC_ENUM_TRAITS_MAX_VALUE says you should pass the largest
possible value, inclusive. But NTP_NUM_EVENT_TYPES is one larger than the
largest possible NTPLoggingEventType.

Review URL: https://codereview.chromium.org/662823002

Cr-Commit-Position: refs/heads/master@{#300248}

chrome/common/ntp_logging_events.h

@@ -8,7 +8,7 @@
 // The different types of events that are logged from the NTP. This enum is used
 // to transfer information from the NTP javascript to the renderer and is not
 // used as a UMA enum histogram's logged value.
-// Note: Keep in sync with browser/resources/local_ntp/most_visited_utils.js
+// Note: Keep in sync with browser/resources/local_ntp/most_visited_util.js
 enum NTPLoggingEventType {
   // The suggestion is coming from the server.
   NTP_SERVER_SIDE_SUGGESTION = 0,
@@ -43,7 +43,7 @@ enum NTPLoggingEventType {
   // The user moused over an NTP tile or title.
   NTP_MOUSEOVER = 9,
 
-  NTP_NUM_EVENT_TYPES
+  NTP_EVENT_TYPE_LAST = NTP_MOUSEOVER
 };
 
 #endif  // CHROME_COMMON_NTP_LOGGING_EVENTS_H_

chrome/common/render_messages.h

@@ -188,7 +188,7 @@ IPC_STRUCT_TRAITS_BEGIN(blink::WebCache::UsageStats)
 IPC_STRUCT_TRAITS_END()
 
 IPC_ENUM_TRAITS_MAX_VALUE(NTPLoggingEventType,
-                          NTP_NUM_EVENT_TYPES)
+                          NTP_EVENT_TYPE_LAST)
 
 IPC_ENUM_TRAITS_MAX_VALUE(WebApplicationInfo::MobileCapable,
                           WebApplicationInfo::MOBILE_CAPABLE_APPLE)

chrome/renderer/searchbox/searchbox_extension.cc

@@ -971,7 +971,7 @@ void SearchBoxExtensionWrapper::LogEvent(
 
   DVLOG(1) << render_view << " LogEvent";
 
-  if (args[0]->Uint32Value() < NTP_NUM_EVENT_TYPES) {
+  if (args[0]->Uint32Value() <= NTP_EVENT_TYPE_LAST) {
     NTPLoggingEventType event =
         static_cast<NTPLoggingEventType>(args[0]->Uint32Value());
     SearchBox::Get(render_view)->LogEvent(event);