Allow specifying base offset when constructing Keyed hydrogen instructions

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 ae8013891f087e07886722b87f2370167177b9f1..6cfe3e17f6f6937690d7cbcc3fcebe6e89a6bfe3 100644
--- a/src/ia32/lithium-ia32.h
+++ b/src/ia32/lithium-ia32.h
@@ -1642,7 +1642,7 @@ class LLoadKeyed V8_FINAL : public LTemplateInstruction<1, 2, 0> {
   DECLARE_HYDROGEN_ACCESSOR(LoadKeyed)
 
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
-  uint32_t additional_index() const { return hydrogen()->index_offset(); }
+  uint32_t base_offset() const { return hydrogen()->base_offset(); }
   bool key_is_smi() {
     return hydrogen()->key()->representation().IsTagged();
   }
@@ -2222,7 +2222,7 @@ class LStoreKeyed V8_FINAL : public LTemplateInstruction<0, 3, 0> {
   DECLARE_HYDROGEN_ACCESSOR(StoreKeyed)
 
   virtual void PrintDataTo(StringStream* stream) V8_OVERRIDE;
-  uint32_t additional_index() const { return hydrogen()->index_offset(); }
+  uint32_t base_offset() const { return hydrogen()->base_offset(); }
   bool NeedsCanonicalization() { return hydrogen()->NeedsCanonicalization(); }
 };