Add trace events for some of telemetry internal functions

common/py_trace_event/py_trace_event/trace_event_impl/meta_class.py

Index: common/py_trace_event/py_trace_event/trace_event_impl/meta_class.py
diff --git a/common/py_trace_event/py_trace_event/trace_event_impl/meta_class.py b/common/py_trace_event/py_trace_event/trace_event_impl/meta_class.py
new file mode 100644
index 0000000000000000000000000000000000000000..4ede79bd338fac7ba31e45d0bbe3b14fba790b96
--- /dev/null
+++ b/common/py_trace_event/py_trace_event/trace_event_impl/meta_class.py
@@ -0,0 +1,16 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import types
+
+from py_trace_event.trace_event_impl import decorators
+
+
+class TracedMetaClass(type):
+  def __new__(cls, name, bases, attrs):
+    for attr_name, attr_value in attrs.iteritems():
+      if isinstance(attr_value, types.FunctionType):
+        attrs[attr_name] = decorators.traced(attr_value)

[perezju, 2016/09/07 09:06:51]

is this tracing every single method? I think that, at the very least, we should
skip methods whose names start with '_'.

[petrcermak, 2016/09/07 09:38:24]

Unless this hinders performance or causes the resulting traces to be too big
(especially the UI), I think it's fine.

+
+    return super(TracedMetaClass, cls).__new__(cls, name, bases, attrs)