Rework standalone to use a synchronous loader that does not invoke Dart code

runtime/vm/service_isolate.cc

Index: runtime/vm/service_isolate.cc
diff --git a/runtime/vm/service_isolate.cc b/runtime/vm/service_isolate.cc
index e65c53962fd11854ce8a37c1ac8b8db358be8cd8..d4d02d7dd4222cfa5bbf93e96768911b4fe0b1d9 100644
--- a/runtime/vm/service_isolate.cc
+++ b/runtime/vm/service_isolate.cc
@@ -363,6 +363,9 @@ class RunServiceTask : public ThreadPool::Task {
 
  protected:
   static void ShutdownIsolate(uword parameter) {
+    if (FLAG_trace_service) {
+      OS::Print("vm-service: ShutdownIsolate\n");
+    }
     Isolate* I = reinterpret_cast<Isolate*>(parameter);
     ASSERT(ServiceIsolate::IsServiceIsolate(I));
     ServiceIsolate::SetServiceIsolate(NULL);
@@ -382,6 +385,10 @@ class RunServiceTask : public ThreadPool::Task {
       if (!error.IsNull() && !error.IsUnwindError()) {
         OS::PrintErr("vm-service: Error: %s\n", error.ToErrorCString());
       }
+      error = I->sticky_error();
+      if (!error.IsNull() && !error.IsUnwindError()) {
+        OS::PrintErr("vm-service: Error: %s\n", error.ToErrorCString());
+      }
       Dart::RunShutdownCallback();
     }
     // Shut the isolate down.