Revert of [turbofan] Speculatively optimize string character access.

src/crankshaft/hydrogen.cc

 // Copyright 2013 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.
 
 #include "src/crankshaft/hydrogen.h"
 
 #include <memory>
 #include <sstream>
 
 #include "src/allocation-site-scopes.h"
@@ skipping 8333 matching lines @@
       HValue* receiver = environment()->ExpressionStackAt(1);
       if (!receiver->IsPhi() || receiver->OperandCount() != 1) return false;
       if (cache->enumerable() != receiver->OperandAt(0)) return false;
       Drop(3);  // key, receiver, function
       Add<HCheckMapValue>(receiver, cache->map());
       ast_context()->ReturnValue(graph()->GetConstantTrue());
       return true;
     }
     case kStringCharCodeAt:
     case kStringCharAt:
-      if (argument_count == 2 && isolate()->IsStringBoundsCheckIntact()) {
+      if (argument_count == 2) {
         HValue* index = Pop();
         HValue* string = Pop();
         Drop(1);  // Function.
         HInstruction* char_code =
             BuildStringCharCodeAt(string, index);
         if (id == kStringCharCodeAt) {
           ast_context()->ReturnInstruction(char_code, ast_id);
           return true;
         }
         AddInstruction(char_code);
@@ skipping 4158 matching lines @@
     isolate()->GetHTracer()->TraceHydrogen(name(), graph_);
   }
 
 #ifdef DEBUG
   graph_->Verify(false);  // No full verify.
 #endif
 }
 
 }  // namespace internal
 }  // namespace v8