Enable chromium trace when atrace is started.

The X event change (https://codereview.chromium.org/23799005/) depends
on the TraceBuffer to handle X events, so we need to enable chromium
trace when using systrace on Android to trace WebView or Chrome.

Part of this change is separated from https://codereview.chromium.org/26675003/
which is not ready to submit before WebView and Android are ready for
combined trace.

BUG=trace-viewer:142

Review URL: https://codereview.chromium.org/26848006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@228813 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 7 insertions, 22 deletions

diff --git a/base/debug/trace_event_impl.cc b/base/debug/trace_event_impl.cc
index e606717..6a0bff9 100644
--- a/base/debug/trace_event_impl.cc
+++ b/base/debug/trace_event_impl.cc
@@ -1212,9 +1212,10 @@ const char* TraceLog::GetCategoryGroupName(
 }
 
 void TraceLog::UpdateCategoryGroupEnabledFlag(int category_index) {
-  bool is_enabled = enable_count_ && category_filter_.IsCategoryGroupEnabled(
-      g_category_groups[category_index]);
-  SetCategoryGroupEnabled(category_index, is_enabled);
+  g_category_group_enabled[category_index] =
+      enable_count_ &&
+      category_filter_.IsCategoryGroupEnabled(
+          g_category_groups[category_index]);
 }
 
 void TraceLog::UpdateCategoryGroupEnabledFlags() {
@@ -1222,22 +1223,6 @@ void TraceLog::UpdateCategoryGroupEnabledFlags() {
     UpdateCategoryGroupEnabledFlag(i);
 }
 
-void TraceLog::SetCategoryGroupEnabled(int category_index, bool is_enabled) {
-  g_category_group_enabled[category_index] =
-      is_enabled ? CATEGORY_GROUP_ENABLED : 0;
-
-#if defined(OS_ANDROID)
-  ApplyATraceEnabledFlag(&g_category_group_enabled[category_index]);
-#endif
-}
-
-bool TraceLog::IsCategoryGroupEnabled(
-    const unsigned char* category_group_enabled) {
-  // On Android, ATrace and normal trace can be enabled independently.
-  // This function checks if the normal trace is enabled.
-  return *category_group_enabled & CATEGORY_GROUP_ENABLED;
-}
-
 const unsigned char* TraceLog::GetCategoryGroupEnabledInternal(
     const char* category_group) {
   DCHECK(!strchr(category_group, '"')) <<
@@ -1700,6 +1685,9 @@ void TraceLog::AddTraceEventWithThreadIdAndTimestamp(
     const unsigned long long* arg_values,
     const scoped_refptr<ConvertableToTraceFormat>* convertable_values,
     unsigned char flags) {
+  if (!*category_group_enabled)
+    return;
+
   DCHECK(name);
 
   if (flags & TRACE_EVENT_FLAG_MANGLE_ID)
@@ -1711,9 +1699,6 @@ void TraceLog::AddTraceEventWithThreadIdAndTimestamp(
                flags);
 #endif
 
-  if (!IsCategoryGroupEnabled(category_group_enabled))
-    return;
-
   TimeTicks now = timestamp - time_offset_;
   TimeTicks thread_now = ThreadNow();