Fix a few nits found by PVS Studio

src/parser.cc

 // 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.
 
 #include "src/v8.h"
 
 #include "src/api.h"
 #include "src/ast.h"
 #include "src/bailout-reason.h"
 #include "src/base/platform/platform.h"
@@ skipping 3185 matching lines @@
         // Parsed for-in loop w/ let declaration.
         return loop;
 
       } else {
         init = variable_statement;
       }
     } else {
       Scanner::Location lhs_location = scanner()->peek_location();
       Expression* expression = ParseExpression(false, CHECK_OK);
       ForEachStatement::VisitMode mode;
-      bool accept_OF = expression->AsVariableProxy();
+      bool accept_OF = expression->IsVariableProxy();
 
       if (CheckInOrOf(accept_OF, &mode)) {
         expression = this->CheckAndRewriteReferenceExpression(
             expression, lhs_location, "invalid_lhs_in_for", CHECK_OK);
 
         ForEachStatement* loop =
             factory()->NewForEachStatement(mode, labels, pos);
         Target target(&this->target_stack_, loop);
 
         Expression* enumerable = ParseExpression(true, CHECK_OK);
@@ skipping 1738 matching lines @@
 
   // We cannot internalize on a background thread; a foreground task will take
   // care of calling Parser::Internalize just before compilation.
 
   if (compile_options() == ScriptCompiler::kProduceParserCache) {
     if (result != NULL) *info_->cached_data() = recorder.GetScriptData();
     log_ = NULL;
   }
 }
 } }  // namespace v8::internal