Add new Dart API call Dart_MakeIsolateRunnable(). This would allow an

runtime/vm/dart_api_impl_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 "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/json.h"
 #include "platform/utils.h"
 #include "vm/class_finalizer.h"
 #include "vm/dart_api_impl.h"
@@ skipping 6263 matching lines @@
   }
   Dart_Isolate isolate = TestCase::CreateTestIsolate();
   ASSERT(isolate != NULL);
   Dart_EnterScope();
   Dart_Handle url = NewString(TestCase::url());
   Dart_Handle source = NewString(kScriptChars);
   Dart_Handle result = Dart_SetLibraryTagHandler(TestCase::library_handler);
   EXPECT_VALID(result);
   Dart_Handle lib = Dart_LoadScript(url, source, 0, 0);
   EXPECT_VALID(lib);
+  Dart_ExitIsolate();
+  bool retval = Dart_MakeIsolateRunnable(isolate);
+  Dart_EnterIsolate(isolate);
+  EXPECT(retval);
   Dart_ExitScope();
   return true;
 }
 
 
 // The error string from the last unhandled exception. This value is only
 // valid until the next Dart_ExitScope().
 static char* last_exception = NULL;
 
 
@@ skipping 1245 matching lines @@
                                    NULL);
   int64_t value = 0;
   result = Dart_IntegerToInt64(result, &value);
   EXPECT_VALID(result);
   EXPECT_EQ(260, value);
 }
 
 #endif  // defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64).
 
 }  // namespace dart