Attribution proto in atoms.

Test: statsd unit tests passed.

Change-Id: I3562319708376ea9d9a14e08382e57590eee7bf1
diff --git a/cmds/statsd/src/atoms.proto b/cmds/statsd/src/atoms.proto
index 968d08f..c81fc1d 100644
--- a/cmds/statsd/src/atoms.proto
+++ b/cmds/statsd/src/atoms.proto
@@ -103,7 +103,11 @@
  * resulted in a particular bit of work being done.
  */
 message WorkSource {
-    // TODO
+    // The uid for a given element in the attribution chain.
+    repeated int32 uid = 1;
+    // The (optional) string tag for an element in the attribution chain. If the
+    // element has no tag, it is encoded as an empty string.
+    repeated string tag = 2;
 }
 
 /*
@@ -413,8 +417,10 @@
     optional string tag = 3;
 
     enum State {
-        OFF = 0;
-        ON = 1;
+        RELEASE = 0;
+        ACQUIRE = 1;
+        CHANGE_RELEASE = 2;
+        CHANGE_ACQUIRE = 3;
     }
     optional State state = 4;
 }
@@ -1066,4 +1072,4 @@
     optional uint64 controller_rx_time_ms = 9;
     // product of current(mA), voltage(V) and time(ms)
     optional uint64 energy_used = 10;
-}
+}
\ No newline at end of file