[strong] Refactor ObjectStrength into a replacement for strong boolean args

src/arm64/lithium-arm64.h

Index: src/arm64/lithium-arm64.h
diff --git a/src/arm64/lithium-arm64.h b/src/arm64/lithium-arm64.h
index 5457f9ceedc2028394262973c6eaade58425fbd0..57611362fdabaec29fa800ece81a8048b5378c16 100644
--- a/src/arm64/lithium-arm64.h
+++ b/src/arm64/lithium-arm64.h
@@ -719,7 +719,7 @@ class LArithmeticT final : public LTemplateInstruction<1, 3, 0> {
 
   DECLARE_HYDROGEN_ACCESSOR(BinaryOperation)
 
-  LanguageMode language_mode() { return hydrogen()->language_mode(); }
+  Strength strength() { return hydrogen()->strength(); }
 
  private:
   Token::Value op_;
@@ -1161,7 +1161,7 @@ class LCmpT final : public LTemplateInstruction<1, 3, 0> {
   DECLARE_CONCRETE_INSTRUCTION(CmpT, "cmp-t")
   DECLARE_HYDROGEN_ACCESSOR(CompareGeneric)
 
-  LanguageMode language_mode() { return hydrogen()->language_mode(); }
+  Strength strength() { return hydrogen()->strength(); }
 
   Token::Value op() const { return hydrogen()->token(); }
 };