Add the RAPPOR directory to the 'metrics' watchlist.

BUG=none
TEST=none
R=asvitkine@chromium.org
NOTRY=true

Review URL: https://codereview.chromium.org/196263002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@256609 0039d316-1c4b-4281-b951-d872f2087c98

WATCHLISTS

@@ -383,6 +383,7 @@
                   '|chrome/browser/extensions/api/metrics_private/'\
                   '|chrome/browser/ui/webui/metrics_handler'\
                   '|content/browser/user_metrics.cc'\
+                  '|components/rappor/'\
                   '|content/public/browser/user_metrics.h'\
                   # Exclude XML files; in particular, histograms.xml.
                   '|tools/metrics/[^.]*([.](?!xml$).*)?$',