Add Brand Code to UMA Uploads

chrome/common/metrics/proto/system_profile.proto

Index: chrome/common/metrics/proto/system_profile.proto
diff --git a/chrome/common/metrics/proto/system_profile.proto b/chrome/common/metrics/proto/system_profile.proto
index 4dbb4762c48e4022b6b67e961081c3b0c678d5ec..e45132c8b537028771936f55bee94fa3d576e725 100644
--- a/chrome/common/metrics/proto/system_profile.proto
+++ b/chrome/common/metrics/proto/system_profile.proto
@@ -40,6 +40,11 @@ message SystemProfileProto {
   // specific.
   optional string app_version = 2;
 
+  // The brand code or distribution tag assigned to a partner, if available.
+  // Brand codes are only available on Windows.  Not every Windows install
+  // though will have a brand code.
+  optional string brand_code = 12;
+
   // The possible channels for an installation, from least to most stable.
   enum Channel {
     CHANNEL_UNKNOWN = 0;  // Unknown channel -- perhaps an unofficial build?