CL under review: https://codereview.chromium.org/1877803002/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/cb18e46a2285abe0bf683ff532bd0909acef6a5e

commit cb18e46a2285abe0bf683ff532bd0909acef6a5e
Author: bartfab <bartfab@chromium.org>
Date: Tue Apr 12 14:42:09 2016

Rename ArcApplicationPolicy to ArcPolicy

We pass more than just app management policies to the ARC runtime.
Consequently, the key that holds the data passed to ARC should have a
more generic name than ArcApplicationPolicy.

BUG= 602197 
TEST=Chrome compiles and runs

TBR=asvitkine@chromium.org (Rietveld being dumb about historgrams.xml)

Review URL: https://codereview.chromium.org/1877803002

Cr-Commit-Position: refs/heads/master@{#386685}

[modify] https://crrev.com/cb18e46a2285abe0bf683ff532bd0909acef6a5e/chrome/browser/chromeos/arc/arc_policy_bridge.cc
[modify] https://crrev.com/cb18e46a2285abe0bf683ff532bd0909acef6a5e/chrome/browser/chromeos/arc/arc_policy_bridge_unittest.cc
[modify] https://crrev.com/cb18e46a2285abe0bf683ff532bd0909acef6a5e/chrome/test/data/policy/policy_test_cases.json
[modify] https://crrev.com/cb18e46a2285abe0bf683ff532bd0909acef6a5e/components/policy/resources/policy_templates.json
[modify] https://crrev.com/cb18e46a2285abe0bf683ff532bd0909acef6a5e/tools/metrics/histograms/histograms.xml