Add microsecond support to DateTime.

runtime/lib/date.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include <time.h>
 
 #include "vm/bootstrap_natives.h"
 
 #include "vm/native_entry.h"
 #include "vm/object.h"
 #include "vm/os.h"
 
 namespace dart {
 
 static int32_t kMaxAllowedSeconds = 2100000000;
 
-DEFINE_NATIVE_ENTRY(DateNatives_timeZoneName, 1) {
+DEFINE_NATIVE_ENTRY(DateTime_timeZoneName, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(
       Integer, dart_seconds, arguments->NativeArgAt(0));
   int64_t seconds = dart_seconds.AsInt64Value();
   if (seconds < 0 || seconds > kMaxAllowedSeconds) {
     Exceptions::ThrowArgumentError(dart_seconds);
   }
   const char* name = OS::GetTimeZoneName(seconds);
   return String::New(name);
 }
 
 
-DEFINE_NATIVE_ENTRY(DateNatives_timeZoneOffsetInSeconds, 1) {
+DEFINE_NATIVE_ENTRY(DateTime_timeZoneOffsetInSeconds, 1) {
   GET_NON_NULL_NATIVE_ARGUMENT(
       Integer, dart_seconds, arguments->NativeArgAt(0));
   int64_t seconds = dart_seconds.AsInt64Value();
   if (seconds < 0 || seconds > kMaxAllowedSeconds) {
     Exceptions::ThrowArgumentError(dart_seconds);
   }
   int offset = OS::GetTimeZoneOffsetInSeconds(seconds);
   return Integer::New(offset);
 }
 
 
-DEFINE_NATIVE_ENTRY(DateNatives_localTimeZoneAdjustmentInSeconds, 0) {
+DEFINE_NATIVE_ENTRY(DateTime_localTimeZoneAdjustmentInSeconds, 0) {
   int adjustment = OS::GetLocalTimeZoneAdjustmentInSeconds();
   return Integer::New(adjustment);
 }
 
 
-DEFINE_NATIVE_ENTRY(DateNatives_currentTimeMillis, 0) {
-  return Integer::New(OS::GetCurrentTimeMillis());
+DEFINE_NATIVE_ENTRY(DateTime_currentTimeMicros, 0) {
+  return Integer::New(OS::GetCurrentTimeMicros());
 }
 
 }  // namespace dart