Address Siva's DBC

runtime/vm/isolate_reload.cc

Index: runtime/vm/isolate_reload.cc
diff --git a/runtime/vm/isolate_reload.cc b/runtime/vm/isolate_reload.cc
index a0542e5907967f49e727f1a8bedce12ef1c2842b..b044daa76b83ba2c2b058fee5229b4e1e95884f0 100644
--- a/runtime/vm/isolate_reload.cc
+++ b/runtime/vm/isolate_reload.cc
@@ -634,8 +634,6 @@ void IsolateReloadContext::Reload(bool force_reload,
   // WEIRD CONTROL FLOW ENDS.
   TIR_Print("---- EXITED TAG HANDLER\n");
 
-  BackgroundCompiler::Enable();
-
   if (result.IsUnwindError()) {
     // We can only propagate errors when there are Dart frames on the stack.
     // TODO(johnmccutchan): Fix dartbug.com/29092.
@@ -725,6 +723,8 @@ void IsolateReloadContext::FinalizeFailedLoad(const Error& error) {
 void IsolateReloadContext::CommonFinalizeTail() {
   ReportOnJSON(js_);
   reload_finalized_ = true;
+  // As a final step, re-enable the background compiler.
+  BackgroundCompiler::Enable();
 }