Begins work on ARM64, first assembler test.

runtime/vm/isolate_test.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.
 
+// TODO(zra): Remove when tests are ready to enable.
+#include "platform/globals.h"
+#if !defined(TARGET_ARCH_ARM64)
+
 #include "platform/assert.h"
 #include "vm/globals.h"
 #include "vm/isolate.h"
 #include "vm/unit_test.h"
 
 namespace dart {
 
 UNIT_TEST_CASE(IsolateCurrent) {
   Isolate* isolate = Isolate::Init(NULL);
   EXPECT_EQ(isolate, Isolate::Current());
@@ skipping 58 matching lines @@
   EXPECT(!Dart_IsError(result));
   // Run until all ports to isolate are closed.
   result = Dart_RunLoop();
   EXPECT_ERROR(result, "Null callback specified for isolate creation");
   EXPECT(Dart_ErrorHasException(result));
   Dart_Handle exception_result = Dart_ErrorGetException(result);
   EXPECT_VALID(exception_result);
 }
 
 }  // namespace dart
+
+#endif  // !defined(TARGET_ARCH_ARM64)