Move sticky_error_ from isolate to thread

runtime/vm/thread.cc

Index: runtime/vm/thread.cc
diff --git a/runtime/vm/thread.cc b/runtime/vm/thread.cc
index adfc4b4ee2bc7baf4f2ab0827e9ed654314a26e9..0fa2d403f06f2e5fa2a59886046097e637225ff6 100644
--- a/runtime/vm/thread.cc
+++ b/runtime/vm/thread.cc
@@ -62,6 +62,7 @@ Thread::Thread(Isolate* isolate)
       deopt_id_(0),
       vm_tag_(0),
       pending_functions_(GrowableObjectArray::null()),
+      sticky_error_(Error::null()),
       REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_INITIALIZERS)
       REUSABLE_HANDLE_LIST(REUSABLE_HANDLE_SCOPE_INIT)
       safepoint_state_(0),
@@ -175,6 +176,27 @@ RawGrowableObjectArray* Thread::pending_functions() {
 }
 
 
+void Thread::clear_pending_functions() {
+  pending_functions_ = GrowableObjectArray::null();
+}
+
+
+RawError* Thread::sticky_error() const {
+  return sticky_error_;
+}
+
+
+void Thread::set_sticky_error(const Error& value) {
+  ASSERT(!value.IsNull());
+  sticky_error_ = value.raw();
+}
+
+
+void Thread::clear_sticky_error() {
+  sticky_error_ = Error::null();
+}
+
+
 bool Thread::EnterIsolate(Isolate* isolate) {
   const bool kIsMutatorThread = true;
   Thread* thread = isolate->ScheduleThread(kIsMutatorThread);
@@ -332,11 +354,10 @@ void Thread::VisitObjectPointers(ObjectPointerVisitor* visitor) {
   // Visit objects in thread specific handles area.
   reusable_handles_.VisitObjectPointers(visitor);
 
-  // Visit the pending functions.
-  if (pending_functions_ != GrowableObjectArray::null()) {
-    visitor->VisitPointer(
-        reinterpret_cast<RawObject**>(&pending_functions_));
-  }
+  visitor->VisitPointer(
+      reinterpret_cast<RawObject**>(&pending_functions_));
+  visitor->VisitPointer(
+      reinterpret_cast<RawObject**>(&sticky_error_));
 
   // Visit the api local scope as it has all the api local handles.
   ApiLocalScope* scope = api_top_scope_;