Fix a couple of minor issues in the Node library

src/node/ext/call_credentials.cc

@@ -32,6 +32,8 @@
  */
 
 #include <node.h>
+#include <nan.h>
+#include <uv.h>
 
 #include "grpc/grpc.h"
 #include "grpc/grpc_security.h"

src/node/ext/timeval.cc

@@ -46,7 +46,7 @@ gpr_timespec MillisecondsToTimespec(double millis) {
   } else if (millis == -std::numeric_limits<double>::infinity()) {
     return gpr_inf_past(GPR_CLOCK_REALTIME);
   } else {
-    return gpr_time_from_micros(static_cast<int64_t>(millis * 1000),
+    return gpr_time_from_micros(static_cast<long>(millis * 1000),
                                 GPR_CLOCK_REALTIME);
   }
 }