[strong] Remove all remainders of strong mode

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 5bdfb0df7d8581b46c33a011947d9069809e7a67..dd61e1ec4c9c73e80627b553356f8748435a94ce 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -5707,8 +5707,7 @@ void SharedFunctionInfo::set_optimization_disabled(bool disable) {
 LanguageMode SharedFunctionInfo::language_mode() {
   STATIC_ASSERT(LANGUAGE_END == 3);
   return construct_language_mode(
-      BooleanBit::get(compiler_hints(), kStrictModeFunction),
-      BooleanBit::get(compiler_hints(), kStrongModeFunction));
+      BooleanBit::get(compiler_hints(), kStrictModeFunction));
 }
 
 
@@ -5719,7 +5718,6 @@ void SharedFunctionInfo::set_language_mode(LanguageMode language_mode) {
   DCHECK(is_sloppy(this->language_mode()) || is_strict(language_mode));
   int hints = compiler_hints();
   hints = BooleanBit::set(hints, kStrictModeFunction, is_strict(language_mode));
-  hints = BooleanBit::set(hints, kStrongModeFunction, is_strong(language_mode));
   set_compiler_hints(hints);
 }