tools/android/loading: rename tracing to tracing_track

tools/android/loading/activity_lens_unittest.py

Index: tools/android/loading/activity_lens_unittest.py
diff --git a/tools/android/loading/activity_lens_unittest.py b/tools/android/loading/activity_lens_unittest.py
index 81c5837b0e728f2be37584e86f345afc3184ad4e..cfa46891f150f781d47b6944a3ae10ce78887814 100644
--- a/tools/android/loading/activity_lens_unittest.py
+++ b/tools/android/loading/activity_lens_unittest.py
@@ -9,20 +9,20 @@ import unittest
 from activity_lens import (ActivityLens, _EventsTree)
 import clovis_constants
 import test_utils
-import tracing
+import tracing_track
 
 
 class ActivityLensTestCase(unittest.TestCase):
   @classmethod
   def _EventsFromRawEvents(cls, raw_events):
-    tracing_track = tracing.TracingTrack(None,
+    track = tracing_track.TracingTrack(None,
         clovis_constants.DEFAULT_CATEGORIES)
-    tracing_track.Handle(
+    track.Handle(
         'Tracing.dataCollected', {'params': {'value': raw_events}})
-    return tracing_track.GetEvents()
+    return track.GetEvents()
 
   def setUp(self):
-    self.tracing_track = tracing.TracingTrack(None,
+    self.track = tracing_track.TracingTrack(None,
         clovis_constants.DEFAULT_CATEGORIES)
 
   def testGetRendererMainThread(self):