- Reduce the number of Isolate::Current() calls.

runtime/vm/allocation.cc

Index: runtime/vm/allocation.cc
===================================================================
--- runtime/vm/allocation.cc	(revision 36483)
+++ runtime/vm/allocation.cc	(working copy)
@@ -14,8 +14,8 @@
   UNREACHABLE();
 }
 
-void* ZoneAllocated::operator new(uword size) {
-  Isolate* isolate = Isolate::Current();
+
+static void* Allocate(uword size, BaseIsolate* isolate) {
   ASSERT(isolate != NULL);
   ASSERT(isolate->current_zone() != NULL);
   if (size > static_cast<uword>(kIntptrMax)) {
@@ -24,4 +24,14 @@
   return reinterpret_cast<void*>(isolate->current_zone()->AllocUnsafe(size));
 }
 
+
+void* ZoneAllocated::operator new(uword size) {
+  return Allocate(size, Isolate::Current());
+}
+
+
+void* ZoneAllocated::operator new(uword size, BaseIsolate* isolate) {
+  return Allocate(size, isolate);
+}
+
 }  // namespace dart