Give isolates names to be used during debugging.

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.
 
 #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();
+  Isolate* isolate = Isolate::Init(NULL);
   EXPECT_EQ(isolate, Isolate::Current());
   isolate->Shutdown();
   EXPECT_EQ(reinterpret_cast<Isolate*>(NULL), Isolate::Current());
   delete isolate;
 }
 
 
 #if defined(TARGET_ARCH_IA32)  // only ia32 can run dart execution tests.
 // Unit test case to verify error during isolate spawning (application classes
 // not loaded into the isolate).
@@ skipping 20 matching lines @@
                                          0,
                                          NULL);
   EXPECT(Dart_IsError(result));
   EXPECT(Dart_ErrorHasException(result));
   Dart_Handle exception_result = Dart_ErrorGetException(result);
   EXPECT_VALID(exception_result);
 }
 #endif  // TARGET_ARCH_IA32.
 
 }  // namespace dart