VM thread shutdown.

runtime/vm/dart_api_impl.cc

Index: runtime/vm/dart_api_impl.cc
diff --git a/runtime/vm/dart_api_impl.cc b/runtime/vm/dart_api_impl.cc
index f3f1f5283960100646aefd336e8a1c9e4c9714f9..5e1105a2ef95e7460d93feee9f3c0531ecd32790 100644
--- a/runtime/vm/dart_api_impl.cc
+++ b/runtime/vm/dart_api_impl.cc
@@ -1254,7 +1254,7 @@ DART_EXPORT const char* Dart_VersionString() {
   return Version::String();
 }
 
-DART_EXPORT bool Dart_Initialize(
+DART_EXPORT char* Dart_Initialize(
     const uint8_t* vm_isolate_snapshot,
     const uint8_t* instructions_snapshot,
     Dart_IsolateCreateCallback create,
@@ -1272,21 +1272,19 @@ DART_EXPORT bool Dart_Initialize(
                                        file_open, file_read, file_write,
                                        file_close, entropy_source);
   if (err_msg != NULL) {
-    OS::PrintErr("Dart_Initialize: %s\n", err_msg);
-    return false;
+    return strdup(err_msg);
   }
-  return true;
+  return NULL;
 }
 
 
-DART_EXPORT bool Dart_Cleanup() {
+DART_EXPORT char* Dart_Cleanup() {
   CHECK_NO_ISOLATE(Isolate::Current());
   const char* err_msg = Dart::Cleanup();
   if (err_msg != NULL) {
-    OS::PrintErr("Dart_Cleanup: %s\n", err_msg);
-    return false;
+    return strdup(err_msg);
   }
-  return true;
+  return NULL;
 }
 
 
@@ -1357,6 +1355,10 @@ DART_EXPORT Dart_Isolate Dart_CreateIsolate(const char* script_uri,
   }
   Isolate* I = Dart::CreateIsolate(isolate_name, *flags);
   free(isolate_name);
+  if (I == NULL) {
+    *error = strdup("Isolate creation failed");
+    return reinterpret_cast<Dart_Isolate>(NULL);
+  }
   {
     Thread* T = Thread::Current();
     StackZone zone(T);