Use TimeUnit enum to specify the bucket size.

Test: all statsd unit test passed

Change-Id: I4f6b80ba2f8c984b06e46e6de6df3e546e99a968
diff --git a/cmds/statsd/src/stats_log_util.h b/cmds/statsd/src/stats_log_util.h
index 1f81860..33303dc 100644
--- a/cmds/statsd/src/stats_log_util.h
+++ b/cmds/statsd/src/stats_log_util.h
@@ -17,6 +17,7 @@
 #pragma once
 
 #include <android/util/ProtoOutputStream.h>
+#include "frameworks/base/cmds/statsd/src/statsd_config.pb.h"
 #include "frameworks/base/cmds/statsd/src/stats_log.pb.h"
 #include "field_util.h"
 
@@ -36,6 +37,9 @@
 void writeFieldValueTreeToStream(const FieldValueMap &fieldValueMap,
     util::ProtoOutputStream* protoOutput);
 
+// Convert the TimeUnit enum to the bucket size in millis.
+int64_t TimeUnitToBucketSizeInMillis(TimeUnit unit);
+
 }  // namespace statsd
 }  // namespace os
 }  // namespace android
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