Cache the isolate pointer in the parser object.

runtime/vm/parser.h

 // Copyright (c) 2012, 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.
 
 #ifndef VM_PARSER_H_
 #define VM_PARSER_H_
 
 #include "include/dart_api.h"
 
 #include "lib/invocation_mirror.h"
 #include "vm/ast.h"
 #include "vm/class_finalizer.h"
 #include "vm/compiler_stats.h"
 #include "vm/scanner.h"
 
 namespace dart {
 
 // Forward declarations.
 class Function;
+class Isolate;
 class LiteralToken;
 class Script;
 class TokenStream;
 
 struct TopLevel;
 class ClassDesc;
 struct MemberDesc;
 struct ParamList;
 struct QualIdent;
 struct CatchParamDesc;
@@ skipping 585 matching lines @@
   void EnsureSavedCurrentContext();
   AstNode* CreateAssignmentNode(AstNode* original, AstNode* rhs);
   AstNode* InsertClosureCallNodes(AstNode* condition);
 
   ConstructorCallNode* CreateConstructorCallNode(
       intptr_t token_pos,
       const AbstractTypeArguments& type_arguments,
       const Function& constructor,
       ArgumentListNode* arguments);
 
+  Isolate* isolate() const { return isolate_; }
+
+  Isolate* isolate_;  // Cached current isolate.
+
   Script& script_;
   TokenStream::Iterator tokens_iterator_;
   Token::Kind token_kind_;  // Cached token kind for current token.
   Block* current_block_;
 
   // is_top_level_ is true if parsing the "top level" of a compilation unit,
   // that is class definitions, function type aliases, global functions,
   // global variables.
   bool is_top_level_;
 
@@ skipping 28 matching lines @@
   // code at all points in the try block where an exit from the block is
   // done using 'return', 'break' or 'continue' statements.
   TryBlocks* try_blocks_list_;
 
   DISALLOW_COPY_AND_ASSIGN(Parser);
 };
 
 }  // namespace dart
 
 #endif  // VM_PARSER_H_