Fix format produced by chart data recorder.

Fix format produced by chart data recorder.

 - dashboard wants a dictionary of dictionaries indexed by name of the
   measurement
 - the uploading logic already serializes the chart data together w/
   metadata, recorder should return Python data structure

R=etiennej@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/dd48bf5ed9763b8b01a495046f73610c6b8e3d88

[ppi, 2015-10-26 14:02:19]

Description was changed from

==========
Fix format produced by chart data recorder.

 - dashboard wants a dictionary of dictionaries indexed by name of the
   measurement
 - the uploading logic already serializes the chart data together w/
   metadata, recorder should return Python data structure
==========

to

==========
Fix format produced by chart data recorder.

 - dashboard wants a dictionary of dictionaries indexed by name of the
   measurement
 - the uploading logic already serializes the chart data together w/
   metadata, recorder should return Python data structure
==========

[ppi, 2015-10-26 14:02:19]

ppi@chromium.org changed reviewers:
+ etiennej@chromium.org

[ppi, 2015-10-26 14:02:31]

Hi Etienne,

ptal.

[etiennej, 2015-10-26 16:36:23]

lgtm

[ppi, 2015-10-27 10:42:01]

Committed patchset #1 (id:1) manually as
dd48bf5ed9763b8b01a495046f73610c6b8e3d88 (presubmit successful).