Enable allocation tracing for classes owned by vm isolate

runtime/vm/class_table.cc

Index: runtime/vm/class_table.cc
diff --git a/runtime/vm/class_table.cc b/runtime/vm/class_table.cc
index 28b7f750c7fe84dba29a540af8798d11c405d3ec..e57178c868d34ff74e326e3a56936af829fa99c7 100644
--- a/runtime/vm/class_table.cc
+++ b/runtime/vm/class_table.cc
@@ -82,12 +82,18 @@ void ClassTable::FreeOldTables() {
 }
 
 
-void ClassTable::TraceAllocationsFor(intptr_t cid, bool trace) {
+void ClassTable::SetTraceAllocationFor(intptr_t cid, bool trace) {
   ClassHeapStats* stats = PreliminaryStatsAt(cid);
   stats->set_trace_allocation(trace);
 }
 
 
+bool ClassTable::TraceAllocationFor(intptr_t cid) {
+  ClassHeapStats* stats = PreliminaryStatsAt(cid);
+  return stats->trace_allocation();
+}
+
+
 void ClassTable::Register(const Class& cls) {
   intptr_t index = cls.id();
   if (index != kIllegalCid) {