Change the thread interface in runtime/platform and use it starting all threads

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/utils.h"
 #include "vm/dart_api_impl.h"
 #include "vm/dart_api_state.h"
 #include "vm/thread.h"
@@ skipping 2952 matching lines @@
   ASSERT(interrupt_count < kInterruptCount);
   return true;
 }
 
 
 TEST_CASE(IsolateInterrupt) {
   Dart_IsolateInterruptCallback saved = Isolate::InterruptCallback();
   Isolate::SetInterruptCallback(IsolateInterruptTestCallback);
 
   sync = new Monitor();
-  Thread* thread = new Thread(BusyLoop_start, 0);
-  EXPECT(thread != NULL);
+  int result = Thread::Start(BusyLoop_start, 0);
+  EXPECT_EQ(0, result);
 
   {
     MonitorLocker ml(sync);
     // Wait for the other isolate to enter main.
     while (!main_entered) {
       ml.Wait();
     }
   }
 
   // Send a number of interrupts to the other isolate. All but the
@@ skipping 24 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  // defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64).
 
 }  // namespace dart