Support int32_t (Java Integer) in KeyValuePair atom

Bug: 116826451
Test: statsd_test + manual verification through logcat
Change-Id: I0157c22033907fea46e26ee4262c723fa8c0b518
diff --git a/stats/atoms.proto b/stats/atoms.proto
index 1e9c354..16cb7ac 100644
--- a/stats/atoms.proto
+++ b/stats/atoms.proto
@@ -200,9 +200,10 @@
 message KeyValuePair {
     optional int32 key = 1;
     oneof value {
-        int64 value_int = 2;
-        string value_str = 3;
-        float value_float = 4;
+        int32 value_int = 2;
+        int64 value_long = 3;
+        string value_str = 4;
+        float value_float = 5;
     }
 }