- Make sure that the threads for dart::bin are in the correct namespace.

runtime/bin/dbg_connection_macos.cc

Index: runtime/bin/dbg_connection_macos.cc
===================================================================
--- runtime/bin/dbg_connection_macos.cc	(revision 39229)
+++ runtime/bin/dbg_connection_macos.cc	(working copy)
@@ -169,7 +169,7 @@
 void DebuggerConnectionImpl::StartHandler(int port_number) {
   ASSERT(DebuggerConnectionHandler::listener_fd_ != -1);
   SetupPollQueue();
-  int result = dart::Thread::Start(&DebuggerConnectionImpl::Handler, 0);
+  int result = Thread::Start(&DebuggerConnectionImpl::Handler, 0);
   if (result != 0) {
     FATAL1("Failed to start debugger connection handler thread: %d\n", result);
   }