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

src/ppc/lithium-ppc.h

Index: src/ppc/lithium-ppc.h
diff --git a/src/ppc/lithium-ppc.h b/src/ppc/lithium-ppc.h
index 0b94645527b967f86fab59d1c389ef3448d41203..2959bffea8681a577d125cbd27f159d01bea1fa1 100644
--- a/src/ppc/lithium-ppc.h
+++ b/src/ppc/lithium-ppc.h
@@ -1131,7 +1131,7 @@ 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(); }
 };
@@ -1495,7 +1495,7 @@ 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_;