Revert of [turbofan] Add language mode to JSCallFunction operator.

src/compiler/js-operator.h

Index: src/compiler/js-operator.h
diff --git a/src/compiler/js-operator.h b/src/compiler/js-operator.h
index c30da196aa134057f317868b1f39af3df1daa938..bdb0c9c7d4411912e8ca2e0e3721223ccd66ed48 100644
--- a/src/compiler/js-operator.h
+++ b/src/compiler/js-operator.h
@@ -21,35 +21,19 @@
 // used as a parameter by JSCallFunction operators.
 class CallFunctionParameters final {
  public:
-  CallFunctionParameters(size_t arity, CallFunctionFlags flags,
-                         LanguageMode language_mode)
-      : bit_field_(ArityField::encode(arity) | FlagsField::encode(flags) |
-                   LanguageModeField::encode(language_mode)) {}
-
-  size_t arity() const { return ArityField::decode(bit_field_); }
-  CallFunctionFlags flags() const { return FlagsField::decode(bit_field_); }
-  LanguageMode language_mode() const {
-    return LanguageModeField::decode(bit_field_);
-  }
-
-  bool operator==(CallFunctionParameters const& that) const {
-    return this->bit_field_ == that.bit_field_;
-  }
-  bool operator!=(CallFunctionParameters const& that) const {
-    return !(*this == that);
-  }
-
- private:
-  friend size_t hash_value(CallFunctionParameters const& p) {
-    return p.bit_field_;
-  }
-
-  typedef BitField<unsigned, 0, 28> ArityField;
-  typedef BitField<CallFunctionFlags, 28, 2> FlagsField;
-  typedef BitField<LanguageMode, 30, 2> LanguageModeField;
-
-  const uint32_t bit_field_;
-};
+  CallFunctionParameters(size_t arity, CallFunctionFlags flags)
+      : arity_(arity), flags_(flags) {}
+
+  size_t arity() const { return arity_; }
+  CallFunctionFlags flags() const { return flags_; }
+
+ private:
+  const size_t arity_;
+  const CallFunctionFlags flags_;
+};
+
+bool operator==(CallFunctionParameters const&, CallFunctionParameters const&);
+bool operator!=(CallFunctionParameters const&, CallFunctionParameters const&);
 
 size_t hash_value(CallFunctionParameters const&);
 
@@ -287,8 +271,7 @@
   const Operator* CreateClosure(Handle<SharedFunctionInfo> shared_info,
                                 PretenureFlag pretenure);
 
-  const Operator* CallFunction(size_t arity, CallFunctionFlags flags,
-                               LanguageMode language_mode);
+  const Operator* CallFunction(size_t arity, CallFunctionFlags flags);
   const Operator* CallRuntime(Runtime::FunctionId id, size_t arity);
 
   const Operator* CallConstruct(int arguments);