[Systrace] Fix systrace clock syncing issue with BattOr.

systrace/profile_chrome/fake_agent_2.py

Index: systrace/profile_chrome/fake_agent_2.py
diff --git a/systrace/profile_chrome/fake_agent_2.py b/systrace/profile_chrome/fake_agent_2.py
index 477b6c750910601a4c7c756a562ec5c2c6f259a0..e0cffcf038c0872ad346b44c7e5a9a004a3a7e3f 100644
--- a/systrace/profile_chrome/fake_agent_2.py
+++ b/systrace/profile_chrome/fake_agent_2.py
@@ -7,6 +7,7 @@ import tempfile
 
 from systrace import trace_result
 from systrace import tracing_agents
+from telemetry.timeline import trace_data as trace_data_module
 
 
 class FakeAgent2(object):
@@ -49,6 +50,9 @@ class FakeAgent2(object):
   def __repr__(self):
     return 'faketracetwo'
 
+  def CollectAgentTraceData(self, builder):
+    builder.AddTraceFor(trace_data_module.CPU_TRACE_DATA, 'fake-contents')
+
 
 class FakeConfig(tracing_agents.TracingConfig):
   def __init__(self):