Introduce the Error object class in the vm. It represents all of the

runtime/vm/dart_api_impl_test.cc

 // Copyright (c) 2011, 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 "include/dart_api.h"
 
 #include "vm/assert.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/thread.h"
 #include "vm/unit_test.h"
 #include "vm/utils.h"
 #include "vm/verifier.h"
 
 namespace dart {
 
 #if defined(TARGET_ARCH_IA32)  // only ia32 can run execution tests.
 
 TEST_CASE(ErrorHandles) {
   const char* kScriptChars =
       "class TestClass  {\n"
       "  static void testMain() {\n"
       "    throw new Exception(\"bad news\");\n"
       "  }\n"
       "}\n";
 
   Dart_Handle lib = TestCase::LoadTestScript(kScriptChars, NULL);
 
   Dart_Handle instance = Dart_True();
-  Dart_Handle error = Api::Error("myerror");
+  Dart_Handle error = Api::NewError("myerror");
   Dart_Handle exception = Dart_InvokeStatic(lib,
                                             Dart_NewString("TestClass"),
                                             Dart_NewString("testMain"),
                                             0,
                                             NULL);
 
   EXPECT(!Dart_IsError(instance));
   EXPECT(Dart_IsError(error));
   EXPECT(Dart_IsError(exception));
 
@@ skipping 2930 matching lines @@
   // We should have received the expected number of interrupts.
   EXPECT_EQ(kInterruptCount, interrupt_count);
 
   // Give the spawned thread enough time to properly exit.
   Isolate::SetInterruptCallback(saved);
 }
 
 #endif  // TARGET_ARCH_IA32.
 
 }  // namespace dart