Create a histogram serialization mechanism in components/metrics

components/metrics.gypi

Index: components/metrics.gypi
diff --git a/components/metrics.gypi b/components/metrics.gypi
index 61e9855f328db750586fbcf32fec7595cefcdc73..6f9b1d59cf5cde90c42364c93197ed6cda6e016b 100644
--- a/components/metrics.gypi
+++ b/components/metrics.gypi
@@ -26,6 +26,13 @@
         'metrics/persisted_logs.cc',
         'metrics/persisted_logs.h',
       ],
+      'conditions': [
+        ['chromeos==1', {
+          'dependencies': [
+            'metrics_chromeos',
+          ],
+        }],
+      ],
     },
     {
       # Protobuf compiler / generator for UMA (User Metrics Analysis).
@@ -46,5 +53,18 @@
       },
       'includes': [ '../build/protoc.gypi' ],
     },
+    {
+      'target_name': 'metrics_chromeos',
+      'type': 'static_library',
+      'sources':[
+        'metrics/chromeos/serialization_utils.cc',
+        'metrics/chromeos/serialization_utils.h',
+        'metrics/chromeos/metric_sample.cc',
+        'metrics/chromeos/metric_sample.h',
+      ],
+      'dependencies': [
+        '../base/base.gyp:base',
+      ],
+    },
   ],
 }