vm-service: Include pauseEvent even when running without debugger support.

runtime/vm/service.cc

Index: runtime/vm/service.cc
diff --git a/runtime/vm/service.cc b/runtime/vm/service.cc
index e209d3b89865c6a7a2c6bd967e984db8f8c6e3c2..ccc5309e1fdf30083f898bffe19852b472797791 100644
--- a/runtime/vm/service.cc
+++ b/runtime/vm/service.cc
@@ -1339,12 +1339,13 @@ static const MethodParameter* get_stack_params[] = {
 
 
 static bool GetStack(Thread* thread, JSONStream* js) {
-  if (!thread->isolate()->compilation_allowed()) {
+  Isolate* isolate = thread->isolate();
+  if (isolate->debugger() == NULL) {
     js->PrintError(kFeatureDisabled,
-        "Cannot get stack when running a precompiled program.");
+                   "Cannot get stack when debugger disabled.");
     return true;
   }
-  Isolate* isolate = thread->isolate();
+  ASSERT(isolate->compilation_allowed());
   DebuggerStackTrace* stack = isolate->debugger()->StackTrace();
   // Do we want the complete script object and complete local variable objects?
   // This is true for dump requests.