Thread/Isolate refactoring: new(Isolate) -> new(Zone)

runtime/vm/scanner.h

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 // Scanner class for the Dart language. The scanner reads source text
 // and produces a stream of tokens which is used by the parser.
 //
 
 #ifndef VM_SCANNER_H_
 #define VM_SCANNER_H_
@@ skipping 164 matching lines @@
     ScanIdentChars(false);
   }
 
   // Reads a number literal.
   void ScanNumber(bool dec_point_seen);
 
   void ScanScriptTag();
 
   CharAtFunc CallCharAt() const { return char_at_func_; }
 
-  Isolate* isolate() const { return isolate_; }
+  Zone* zone() const { return zone_; }
 
   static void PrintTokens(const GrowableTokenStream& ts);
 
   TokenDescriptor current_token_;  // Current token.
   TokenDescriptor newline_token_;  // Newline token.
   TokenDescriptor empty_string_token_;  // Token for "".
   const String& source_;           // The source text being tokenized.
   intptr_t source_length_;         // The length of the source text.
   intptr_t lookahead_pos_;         // Position of lookahead character
                                    // within source_.
   intptr_t token_start_;           // Begin of current token in src_.
   int32_t c0_;                     // Lookahead character.
   bool newline_seen_;              // Newline before current token.
   intptr_t prev_token_line_;       // Line number of the previous token.
 
   // The following fields keep track whether we are scanning a string literal
   // and its interpolated expressions.
   ScanContext* saved_context_;
   int32_t string_delimiter_;
   bool string_is_multiline_;
   int brace_level_;
 
   const String& private_key_;
 
   SourcePosition c0_pos_;      // Source position of lookahead character c0_.
 
   const CharAtFunc char_at_func_;
 
-  Isolate* isolate_;
+  Zone* zone_;
 
   static KeywordTable keywords_[Token::kNumKeywords];
   static int keywords_char_offset_[kNumLowercaseChars];
 };
 
 
 }  // namespace dart
 
 #endif  // VM_SCANNER_H_