Expose UseCounter::Feature enum out of blink as WebFeature

WATCHLISTS

Index: WATCHLISTS
diff --git a/WATCHLISTS b/WATCHLISTS
index f036247c908ed260e01544b3794b71f9c01d9c09..378de58b55a3fec0392edb20f971adbd010f2c7d 100644
--- a/WATCHLISTS
+++ b/WATCHLISTS
@@ -1158,6 +1158,10 @@
                   '|ios/chrome/app/strings/ios(_.+)*_strings.grd'\
                   '|ui/strings/ui_strings.grd',
     },
+    {
+    'use_counter_features': {
+      'filepath': 'third_party/WebKit/public/platform/UseCounterFeature.def',
+    },
     'valgrind': {
       'filepath': 'valgrind',
     },
@@ -2272,6 +2276,7 @@
     'ui_display_win': ['robliao+watch@chromium.org'],
     'ui_resources': ['oshima+watch@chromium.org'],
     'ui_strings': ['srahim+watch@chromium.org'],
+    'use_counter_features': ['lunalu@chromium.org'],
     'valgrind': ['bruening+watch@chromium.org',
                  'glider+watch@chromium.org'],
     'version_assembly': ['caitkp+watch@chromium.org',