Pretenure heap number in high promotino mode if a store requires a mutable...

Pretenure heap number in high promotino mode if a store requires a mutable heap number to be allocated.

BUG=
R=mstarzinger@chromium.org

Review URL: https://codereview.chromium.org/21501002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@16004 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/hydrogen.cc

@@ -4531,7 +4531,8 @@ HInstruction* HOptimizedGraphBuilder::BuildStoreNamedField(
       NoObservableSideEffectsScope no_side_effects(this);
       HInstruction* heap_number_size = Add<HConstant>(HeapNumber::kSize);
       HInstruction* heap_number = Add<HAllocate>(heap_number_size,
-          HType::HeapNumber(), NOT_TENURED, HEAP_NUMBER_TYPE);
+          HType::HeapNumber(), isolate()->heap()->GetPretenureMode(),
+          HEAP_NUMBER_TYPE);
       AddStoreMapConstant(heap_number, isolate()->factory()->heap_number_map());
       Add<HStoreNamedField>(heap_number, HObjectAccess::ForHeapNumberValue(),
                             value);