Set tracing categories explicitly in Clovis and Sandwich

tools/android/loading/sandwich_runner.py

Index: tools/android/loading/sandwich_runner.py
diff --git a/tools/android/loading/sandwich_runner.py b/tools/android/loading/sandwich_runner.py
index 9ed8258f63ecbc827a404831d7ccfafe14b7ad3b..693380c31a04ce88928049b13d805160a9e83017 100644
--- a/tools/android/loading/sandwich_runner.py
+++ b/tools/android/loading/sandwich_runner.py
@@ -33,6 +33,18 @@ MEMORY_DUMP_CATEGORY = 'disabled-by-default-memory-infra'
 # network condition.
 _DEVTOOLS_TIMEOUT = 60
 
+# Categories to enable or disable for all traces collected. Disabled categories
+# are prefixed with '-'.
+_TRACING_CATEGORIES = [
+  'blink',
+  'blink.net',
+  'blink.user_timing',
+  'devtools.timeline',
+  'java',
+  'toplevel',
+  'v8',
+  '-cc',  # A lot of unnecessary events are enabled by default in "cc".
+]

[gabadie, 2016/06/06 16:17:30]

We might probably be able to get rid of devtools.timeline, v8, toplevel and
java. Or have I missed something?

Can be deferred to a separate CL.

[pasko, 2016/06/06 17:30:52]

If we remove toplevel, we would not be able to reason about what happened by
looking at the traces in the traceviewer.

Same for v8: it tells us when the blink thread was busy executing javascript,
which is an important bit of data.

as for 'java' - I did not see any events in our traces in this category, which
means:
1. there is probably a bug somewhere
2. we can easily remove it

I just removed it in the next patchset.

[gabadie, 2016/06/06 17:37:10]

Nice.

 
 def _CleanArtefactsFromPastRuns(output_directories_path):
   """Cleans artifacts generated from past run in the output directory.
@@ -146,13 +158,23 @@ class SandwichRunner(object):
         os.makedirs(run_path)
     self._chrome_ctl.SetNetworkEmulation(
         self._GetEmulatorNetworkCondition('browser'))
-    additional_categories = []
+    categories = _TRACING_CATEGORIES
     if self.record_memory_dumps:
-      additional_categories = [MEMORY_DUMP_CATEGORY]
+      categories += [MEMORY_DUMP_CATEGORY]
     # TODO(gabadie): add a way to avoid recording a trace.
     with self._chrome_ctl.Open() as connection:
       if clear_cache:
         connection.ClearCache()
+
+      # Binds all parameters of RecordUrlNavigation() to avoid repetition.
+      def RecordTrace():
+        return loading_trace.LoadingTrace.RecordUrlNavigation(
+            url=self.url,
+            connection=connection,
+            chrome_metadata=self._chrome_ctl.ChromeMetadata(),
+            categories=categories,
+            timeout_seconds=_DEVTOOLS_TIMEOUT)
+
       if run_path is not None and self.record_video:
         device = self._chrome_ctl.GetDevice()
         if device is None:
@@ -160,19 +182,9 @@ class SandwichRunner(object):
         video_recording_path = os.path.join(run_path, VIDEO_FILENAME)
         with device_setup.RemoteSpeedIndexRecorder(device, connection,
                                                    video_recording_path):
-          trace = loading_trace.LoadingTrace.RecordUrlNavigation(
-              url=self.url,
-              connection=connection,
-              chrome_metadata=self._chrome_ctl.ChromeMetadata(),
-              additional_categories=additional_categories,
-              timeout_seconds=_DEVTOOLS_TIMEOUT)
+          trace = RecordTrace()
       else:
-        trace = loading_trace.LoadingTrace.RecordUrlNavigation(
-            url=self.url,
-            connection=connection,
-            chrome_metadata=self._chrome_ctl.ChromeMetadata(),
-            additional_categories=additional_categories,
-            timeout_seconds=_DEVTOOLS_TIMEOUT)
+        trace = RecordTrace()
     if run_path is not None:
       trace_path = os.path.join(run_path, TRACE_FILENAME)
       trace.ToJsonFile(trace_path)