Use immediates when possible for HBoundsCheck and HLoadKeyedFastElement

src/ia32/lithium-ia32.h

Index: src/ia32/lithium-ia32.h
diff --git a/src/ia32/lithium-ia32.h b/src/ia32/lithium-ia32.h
index efa048dd24baa416d55a5bd6a6621573420f47e6..9d37821219de2ab33464f1e39e0dfff1b90dc573 100644
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -2248,7 +2248,11 @@ class LChunkBuilder BASE_EMBEDDED {
   template<int I, int T>
       LInstruction* DefineFixedDouble(LTemplateInstruction<1, I, T>* instr,
                                       XMMRegister reg);
+  // Must be called for any instruction that can deoptimize (unless
+  // |MarkAsCall| is called with CAN_DEOPTIMIZE_EAGERLY, which implies this).
   LInstruction* AssignEnvironment(LInstruction* instr);
+  // Must be called for any instruction that can trigger a GC (unless
+  // |MarkAsCall| is called, which implies this).
   LInstruction* AssignPointerMap(LInstruction* instr);
 
   enum CanDeoptimize { CAN_DEOPTIMIZE_EAGERLY, CANNOT_DEOPTIMIZE_EAGERLY };