[runtime] Add %ToString and %_ToString and remove the TO_STRING builtin.

src/runtime/runtime.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_RUNTIME_RUNTIME_H_
 #define V8_RUNTIME_RUNTIME_H_
 
 #include "src/allocation.h"
 #include "src/objects.h"
 #include "src/unicode.h"
@@ skipping 478 matching lines @@
   F(IsStrong, 1, 1)                                  \
   F(ClassOf, 1, 1)                                   \
   F(DefineGetterPropertyUnchecked, 4, 1)             \
   F(DefineSetterPropertyUnchecked, 4, 1)             \
   F(ToObject, 1, 1)                                  \
   F(ToPrimitive, 1, 1)                               \
   F(ToPrimitive_Number, 1, 1)                        \
   F(ToPrimitive_String, 1, 1)                        \
   F(OrdinaryToPrimitive, 2, 1)                       \
   F(ToNumber, 1, 1)                                  \
+  F(ToString, 1, 1)                                  \
   F(ToName, 1, 1)                                    \
   F(StrictEquals, 2, 1)                              \
   F(InstanceOf, 2, 1)                                \
   F(HasInPrototypeChain, 2, 1)
 
 
 #define FOR_EACH_INTRINSIC_OBSERVE(F)            \
   F(IsObserved, 1, 1)                            \
   F(SetIsObserved, 1, 1)                         \
   F(EnqueueMicrotask, 1, 1)                      \
@@ skipping 742 matching lines @@
 inline bool Runtime::AtomicIsLockFree(uint32_t size) {
   return size == 1 || size == 2 || size == 4;
 }
 
 #endif
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_RUNTIME_RUNTIME_H_