[counters] Use separate counters for background parsing

src/parsing/parser.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_PARSING_PARSER_H_
 #define V8_PARSING_PARSER_H_
 
 #include "src/ast/ast.h"
 #include "src/ast/scopes.h"
 #include "src/base/compiler-specific.h"
@@ skipping 1127 matching lines @@
 
   ScriptCompiler::CompileOptions compile_options_;
   ParseData* cached_parse_data_;
 
   PendingCompilationErrorHandler pending_error_handler_;
 
   // Other information which will be stored in Parser and moved to Isolate after
   // parsing.
   int use_counts_[v8::Isolate::kUseCounterFeatureCount];
   int total_preparse_skipped_;
-  bool parsing_on_main_thread_;
   bool allow_lazy_;
   ParserLogger* log_;
 };
 
 // ----------------------------------------------------------------------------
 // Target is a support class to facilitate manipulation of the
 // Parser's target_stack_ (the stack of potential 'break' and
 // 'continue' statement targets). Upon construction, a new target is
 // added; it is removed upon destruction.
 
@@ skipping 29 matching lines @@
 
  private:
   ParserTarget** variable_;
   ParserTarget* previous_;
 };
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_PARSING_PARSER_H_