telemetry: Add thread time to telmetry timeline.

tools/telemetry/telemetry/core/timeline/counter.py

Index: tools/telemetry/telemetry/core/timeline/counter.py
diff --git a/tools/telemetry/telemetry/core/timeline/counter.py b/tools/telemetry/telemetry/core/timeline/counter.py
index f21f5162fe487a3979ba96c3816ca9919993c1b4..a35bf2ba7ad63b23adc01f42ed79c3b54da097df 100644
--- a/tools/telemetry/telemetry/core/timeline/counter.py
+++ b/tools/telemetry/telemetry/core/timeline/counter.py
@@ -32,6 +32,18 @@ class CounterSample(object):
   def end(self):
     return self.start
 
+  @property
+  def thread_start(self):
+    return None
+
+  @property
+  def thread_duration(self):
+    return None
+
+  @property
+  def thread_end(self):
+    return None
+
 
 class Counter(event_container.TimelineEventContainer):
   """ Stores all the samples for a given counter.