[es8] Prepare explicit tail calls (STC) for staging with implicit tail calls (PTC).

src/parsing/preparser.cc

 // Copyright 2011 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 <cmath>
 
 #include "src/allocation.h"
 #include "src/base/logging.h"
 #include "src/conversions-inl.h"
 #include "src/conversions.h"
@@ skipping 997 matching lines @@
         ParseBlock(CHECK_OK);
       }
     }
     catch_block_exists = true;
     tok = peek();
   }
   if (tok == Token::FINALLY) {
     Consume(Token::FINALLY);
     ParseBlock(CHECK_OK);
     if (FLAG_harmony_explicit_tailcalls && catch_block_exists &&
-        !tail_call_expressions_in_catch_block.is_empty()) {
+        tail_call_expressions_in_catch_block.has_explicit_tail_calls()) {
       // TODO(ishell): update chapter number.
       // ES8 XX.YY.ZZ
       ReportMessageAt(tail_call_expressions_in_catch_block.location(),
                       MessageTemplate::kUnexpectedTailCallInCatchBlock);
       *ok = false;
       return Statement::Default();
     }
   }
   return Statement::Default();
 }
@@ skipping 195 matching lines @@
   }
   Expect(Token::RBRACE, CHECK_OK);
   return PreParserExpression::Default();
 }
 
 #undef CHECK_OK
 
 
 }  // namespace internal
 }  // namespace v8