[Isolates] Merge 7051:7083 from bleeding_edge to isolates.

src/ia32/full-codegen-ia32.cc

Index: src/ia32/full-codegen-ia32.cc
===================================================================
--- src/ia32/full-codegen-ia32.cc	(revision 7083)
+++ src/ia32/full-codegen-ia32.cc	(working copy)
@@ -199,10 +199,13 @@
     // stack frame was an arguments adapter frame.
     ArgumentsAccessStub stub(ArgumentsAccessStub::NEW_OBJECT);
     __ CallStub(&stub);
-    __ mov(ecx, eax);  // Duplicate result.
+
+    Variable* arguments_shadow = scope()->arguments_shadow();
+    if (arguments_shadow != NULL) {
+      __ mov(ecx, eax);  // Duplicate result.
+      Move(arguments_shadow->AsSlot(), ecx, ebx, edx);
+    }
     Move(arguments->AsSlot(), eax, ebx, edx);
-    Slot* dot_arguments_slot = scope()->arguments_shadow()->AsSlot();
-    Move(dot_arguments_slot, ecx, ebx, edx);
   }
 
   if (FLAG_trace) {