Revert of [crankshaft] Protect against deopt loops from string length overflows.

src/isolate-inl.h

 // Copyright 2015 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_INL_H_
 #define V8_ISOLATE_INL_H_
 
 #include "src/isolate.h"
 #include "src/objects-inl.h"
 
@@ skipping 129 matching lines @@
   Cell* species_cell = heap()->species_protector();
   return species_cell->value()->IsSmi() &&
          Smi::cast(species_cell->value())->value() == kArrayProtectorValid;
 }
 
 bool Isolate::IsHasInstanceLookupChainIntact() {
   PropertyCell* has_instance_cell = heap()->has_instance_protector();
   return has_instance_cell->value() == Smi::FromInt(kArrayProtectorValid);
 }
 
-bool Isolate::IsStringLengthOverflowIntact() {
-  PropertyCell* has_instance_cell = heap()->string_length_protector();
-  return has_instance_cell->value() == Smi::FromInt(kArrayProtectorValid);
-}
-
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ISOLATE_INL_H_