Revert of [turbofan] Speculatively optimize string character access.

src/isolate.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_ISOLATE_H_
 #define V8_ISOLATE_H_
 
 #include <memory>
 #include <queue>
 
@@ skipping 1023 matching lines @@
 
   Map* get_initial_js_array_map(ElementsKind kind);
 
   static const int kProtectorValid = 1;
   static const int kProtectorInvalid = 0;
 
   bool IsFastArrayConstructorPrototypeChainIntact();
   inline bool IsArraySpeciesLookupChainIntact();
   bool IsIsConcatSpreadableLookupChainIntact();
   bool IsIsConcatSpreadableLookupChainIntact(JSReceiver* receiver);
-  inline bool IsStringBoundsCheckIntact();
   inline bool IsStringLengthOverflowIntact();
   inline bool IsArrayIteratorLookupChainIntact();
 
   // Avoid deopt loops if fast Array Iterators migrate to slow Array Iterators.
   inline bool IsFastArrayIterationIntact();
 
   // Make sure we do check for neutered array buffers.
   inline bool IsArrayBufferNeuteringIntact();
 
   // On intent to set an element in object, make sure that appropriate
@@ skipping 760 matching lines @@
 
   EmbeddedVector<char, 128> filename_;
   FILE* file_;
   int scope_depth_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ISOLATE_H_