Consistently make the bounds check for AccessArgumentsAt explicit.

src/ia32/lithium-ia32.cc

Index: src/ia32/lithium-ia32.cc
diff --git a/src/ia32/lithium-ia32.cc b/src/ia32/lithium-ia32.cc
index 38e7480d3df87c3222972c67dbb26ae1f590eb06..4b08a6dc68259b1056a0fae51394801c81d1bc0f 100644
--- a/src/ia32/lithium-ia32.cc
+++ b/src/ia32/lithium-ia32.cc
@@ -2279,12 +2279,10 @@ LInstruction* LChunkBuilder::DoArgumentsObject(HArgumentsObject* instr) {
 
 
 LInstruction* LChunkBuilder::DoAccessArgumentsAt(HAccessArgumentsAt* instr) {
-  LOperand* arguments = UseRegister(instr->arguments());
+  LOperand* args = UseRegister(instr->arguments());
   LOperand* length = UseTempRegister(instr->length());
   LOperand* index = Use(instr->index());
-  LAccessArgumentsAt* result =
-      new(zone()) LAccessArgumentsAt(arguments, length, index);
-  return AssignEnvironment(DefineAsRegister(result));
+  return DefineAsRegister(new(zone()) LAccessArgumentsAt(args, length, index));
 }