Cleanup of page_measurement_results object

Cleanup of page_measurement_results object

This patch introduces telemetry.value, which factors out the different kinds of
data collected by telemetry benchmarks, currently scalar values, lists of
scalar values, and histograms. This factoring provides mechanisms for combining
together values --- value summarization, which was previously the job of the
results objects, is now part of the value system.

The actual interface between the page_measurement_results object and the
rest of telemetry is unchanged. A values_backcompat module exists to convert
the old interface to the new interface. A followup patch can remove this
backcompat path.

Most discussion of this is on https://codereview.chromium.org/27486002/

BUG=306944
Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=236907

[tonyg, 2013-11-22 22:08:07]

lgtm

giddyup :)

[commit-bot: I haz the power, 2013-11-22 22:16:33]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/nduca@chromium.org/83813003/1

[commit-bot: I haz the power, 2013-11-23 01:37:08]

Change committed as 236907