- Write the coverage data to a file instead of printing to stdout.

runtime/vm/coverage.h

 // Copyright (c) 2013, 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_COVERAGE_H_
 #define VM_COVERAGE_H_
 
 #include "vm/allocation.h"
 #include "vm/flags.h"
 
 namespace dart {
 
-DECLARE_FLAG(bool, print_coverage);
+DECLARE_FLAG(charp, coverage_dir);
 
 // Forward declarations.
 class Class;
 class Isolate;
 class JSONArray;
 
 class CodeCoverage : public AllStatic {
  public:
-  static void Print(Isolate* isolate);
+  static void Write(Isolate* isolate);
 
  private:
   static void PrintClass(const Class& cls, const JSONArray& arr);
 };
 
 }  // namespace dart
 
 #endif  // VM_COVERAGE_H_