Add includes for missing definitions of size_t and uint32_t.

flow/Hash3.h

@@ -2,6 +2,9 @@
 #define FLOW_HASH3_H
 #pragma once
 
+#include <stdint.h>
+#include <stddef.h>
+
 // Prototypes for Bob Jenkins' "lookup3" hash
 // See Hash3.c for detailed documentation
 

flow/Stats.h

@@ -33,6 +33,8 @@ MyCounters() : foo("foo", cc), bar("bar", cc), baz("baz", cc) {}
 
 */
 
+#include <cstdint>
+#include <cstddef>
 #include "flow.h"
 #include "TDMetric.actor.h"
 
@@ -110,4 +112,4 @@ static void specialCounter(CounterCollection& collection, std::string const& nam
 
 Future<Void> traceCounters(std::string const& traceEventName, UID const& traceEventID, double const& interval, CounterCollection* const& counters, std::string const& trackLatestName = std::string());
 
-#endif
+#endif