Fix native traces to appear in systrace.py

Previously traces from the native side would only get included if the
callsite had not previously cached the category enabled result. (e.g.
worked well if tracing enabled prior to app launch, but not for apps
that had been running a while).

BUG=

Review URL: https://chromiumcodereview.appspot.com/14940015

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@199862 0039d316-1c4b-4281-b951-d872f2087c98

base/debug/trace_event_android.cc

@@ -67,8 +67,11 @@ void TraceLog::StartATrace() {
   AutoLock lock(lock_);
   if (g_atrace_fd == -1) {
     g_atrace_fd = open(kATraceMarkerFile, O_WRONLY);
-    if (g_atrace_fd == -1)
+    if (g_atrace_fd == -1) {
       LOG(WARNING) << "Couldn't open " << kATraceMarkerFile;
+    } else {
+      EnableIncludedCategoryGroups();
+    }
   }
 }
 
@@ -77,6 +80,7 @@ void TraceLog::StopATrace() {
   if (g_atrace_fd != -1) {
     close(g_atrace_fd);
     g_atrace_fd = -1;
+    EnableIncludedCategoryGroups();
   }
 }
 

base/debug/trace_event_impl.cc

@@ -831,6 +831,10 @@ void TraceLog::EnableIncludedCategoryGroup(int category_index) {
       g_category_groups[category_index]);
   g_category_group_enabled[category_index] =
       is_enabled ? TraceLog::CATEGORY_ENABLED : 0;
+
+#if defined(OS_ANDROID)
+  ApplyATraceEnabledFlag(&g_category_group_enabled[category_index]);
+#endif
 }
 
 void TraceLog::EnableIncludedCategoryGroups() {
@@ -880,9 +884,6 @@ const unsigned char* TraceLog::GetCategoryGroupEnabledInternal(
           &g_category_group_enabled[g_category_categories_exhausted];
     }
   }
-#if defined(OS_ANDROID)
-  ApplyATraceEnabledFlag(category_group_enabled);
-#endif
   return category_group_enabled;
 }