telemetry: Create a helper class to quickly extend profiles.

tools/telemetry/telemetry/page/profile_generator.py

Index: tools/telemetry/telemetry/page/profile_generator.py
diff --git a/tools/telemetry/telemetry/page/profile_generator.py b/tools/telemetry/telemetry/page/profile_generator.py
index 4d7bf7d75d2cf385c747a59309e3c57ec7eb71ea..21e20c8c09ca169c337d3791c07ff08c55c5cc39 100644
--- a/tools/telemetry/telemetry/page/profile_generator.py
+++ b/tools/telemetry/telemetry/page/profile_generator.py
@@ -33,9 +33,9 @@ def _DiscoverProfileCreatorClasses():
   # Remove '_creator' suffix from keys.
   profile_creators = {}
   for test_name, test_class in profile_creators_unfiltered.iteritems():
-    assert test_name.endswith('_creator')
-    test_name = test_name[:-len('_creator')]
-    profile_creators[test_name] = test_class
+    if test_name.endswith('_creator'):

[nednguyen, 2015/02/12 02:10:54]

Why this file change? I thought we both agree that we won't try to make this
patch runnable?

[erikchen, 2015/02/12 02:26:07]

Without this change, small_profile_creator won't work, as the assertion will
evaluate to false.

[nednguyen, 2015/02/12 03:17:59]

Does that mean it's currently broken? But why does the assertion fail anyway?
Isn't small_profile_creator name ends with '_creator'? 

[erikchen, 2015/02/12 03:38:35]

The previous code goes through the profile_creator directory and asserts that
all discovered files end with _creator. I'm adding new files to the directory
that don't end in _creator.

[nednguyen, 2015/02/12 16:45:52]

I still don't understand. Line 30 shows that profile_creators_unfiltered should
only contain classes whose base class is profile_creator.ProfileCreator. Your 
FastNavigationProfileExtender shouldn't be one of those.

Or is the discover's implementation buggy here?

[erikchen, 2015/02/12 18:16:46]

The implementation is not buggy. This change is not actually required - I was
mistaken. I've been ferrying patches between multiple CLs, and I managed to
confuse myself.

+      test_name = test_name[:-len('_creator')]
+      profile_creators[test_name] = test_class
   return profile_creators