MIPS: Introduce LanguageMode, drop StrictMode.

src/mips64/lithium-mips64.h

Index: src/mips64/lithium-mips64.h
diff --git a/src/mips64/lithium-mips64.h b/src/mips64/lithium-mips64.h
index a50fa51616d16b118c9996b0c576d233ecf97f3b..afc84efb8f380c25dd158f67596595e25c8cac4a 100644
--- a/src/mips64/lithium-mips64.h
+++ b/src/mips64/lithium-mips64.h
@@ -2177,7 +2177,7 @@ class LStoreNamedGeneric FINAL : public LTemplateInstruction<0, 3, 0> {
   void PrintDataTo(StringStream* stream) OVERRIDE;
 
   Handle<Object> name() const { return hydrogen()->name(); }
-  StrictMode strict_mode() { return hydrogen()->strict_mode(); }
+  LanguageMode language_mode() { return hydrogen()->language_mode(); }
 };
 
 
@@ -2234,7 +2234,7 @@ class LStoreKeyedGeneric FINAL : public LTemplateInstruction<0, 4, 0> {
 
   void PrintDataTo(StringStream* stream) OVERRIDE;
 
-  StrictMode strict_mode() { return hydrogen()->strict_mode(); }
+  LanguageMode language_mode() { return hydrogen()->language_mode(); }
 };