Introduce LanguageMode, drop StrictMode.

src/ic/arm/ic-arm.cc

Index: src/ic/arm/ic-arm.cc
diff --git a/src/ic/arm/ic-arm.cc b/src/ic/arm/ic-arm.cc
index 0c9e1c3736fb80624c12be8d1f5a48e11d9a5dc3..093a7c1bb2cd360c5453793aa26ee84d271aa5b3 100644
--- a/src/ic/arm/ic-arm.cc
+++ b/src/ic/arm/ic-arm.cc
@@ -722,7 +722,7 @@ static void KeyedStoreGenerateMegamorphicHelper(
 
 
 void KeyedStoreIC::GenerateMegamorphic(MacroAssembler* masm,
-                                       StrictMode strict_mode) {
+                                       LanguageMode language_mode) {
   // ---------- S t a t e --------------
   //  -- r0     : value
   //  -- r1     : key
@@ -777,7 +777,7 @@ void KeyedStoreIC::GenerateMegamorphic(MacroAssembler* masm,
   // r0: value.
   // r1: key.
   // r2: receiver.
-  PropertyICCompiler::GenerateRuntimeSetProperty(masm, strict_mode);
+  PropertyICCompiler::GenerateRuntimeSetProperty(masm, language_mode);
   // Never returns to here.
 
   __ bind(&maybe_name_key);