Tracing: Add metadata indicating whether we have a high-resolution clock available

content/browser/tracing/tracing_controller_impl.cc

Index: content/browser/tracing/tracing_controller_impl.cc
diff --git a/content/browser/tracing/tracing_controller_impl.cc b/content/browser/tracing/tracing_controller_impl.cc
index 4b9f4556d6fc07acecbe48499eedc281cf17c853..83d6c91ab368ffeb9cc133c9a18143ee4dc30f41 100644
--- a/content/browser/tracing/tracing_controller_impl.cc
+++ b/content/browser/tracing/tracing_controller_impl.cc
@@ -167,6 +167,9 @@ void TracingControllerImpl::OnEnableRecordingDone(
     const EnableRecordingDoneCallback& callback) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
 
+  TRACE_EVENT_API_ADD_METADATA_EVENT("IsTimeTicksHighResolution", "value",
+                                     base::TimeTicks::IsHighResolution());
+
   // Notify all child processes.
   for (TraceMessageFilterSet::iterator it = trace_message_filters_.begin();
       it != trace_message_filters_.end(); ++it) {