Introduce LanguageMode, drop StrictMode.

src/ic/ia32/ic-ia32.cc

Index: src/ic/ia32/ic-ia32.cc
diff --git a/src/ic/ia32/ic-ia32.cc b/src/ic/ia32/ic-ia32.cc
index c8e72155dd1f5daad2891ed3e3247c6a63e2a3ae..54fd053eaf033a5a0c5b0c09a395661f18d98e92 100644
--- a/src/ic/ia32/ic-ia32.cc
+++ b/src/ic/ia32/ic-ia32.cc
@@ -612,7 +612,7 @@ static void KeyedStoreGenerateMegamorphicHelper(
 
 
 void KeyedStoreIC::GenerateMegamorphic(MacroAssembler* masm,
-                                       StrictMode strict_mode) {
+                                       LanguageMode language_mode) {
   // Return address is on the stack.
   Label slow, fast_object, fast_object_grow;
   Label fast_double, fast_double_grow;
@@ -649,7 +649,7 @@ void KeyedStoreIC::GenerateMegamorphic(MacroAssembler* masm,
 
   // Slow case: call runtime.
   __ bind(&slow);
-  PropertyICCompiler::GenerateRuntimeSetProperty(masm, strict_mode);
+  PropertyICCompiler::GenerateRuntimeSetProperty(masm, language_mode);
   // Never returns to here.
 
   __ bind(&maybe_name_key);