Track JS allocations as they arrive with no affection on performance when tracking is switched off

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index ae8a0b58ba87939a2adf6eb2298826082843cb27..4c0062e17e647cf26a1a29eb2e4d77d0cd17fb32 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -1316,6 +1316,21 @@ ExternalReference ExternalReference::address_of_the_hole_nan() {
 }
 
 
+ExternalReference ExternalReference::is_tracking_allocations_address(
+  Isolate* isolate) {
+  return ExternalReference(
+    isolate->heap_profiler()->is_tracking_allocations_address());
+}
+
+
+ExternalReference ExternalReference::record_object_allocation_function(
+  Isolate* isolate) {
+  return ExternalReference(
+    Redirect(isolate,
+             FUNCTION_ADDR(HeapProfiler::RecordObjectAllocationFromMasm)));
+}
+
+
 #ifndef V8_INTERPRETED_REGEXP
 
 ExternalReference ExternalReference::re_check_stack_guard_state(