Support more configurability in GN toolchains

tools/gn/test_with_scope.h

 // Copyright (c) 2013 The Chromium 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 TOOLS_GN_TEST_WITH_SCOPE_H_
 #define TOOLS_GN_TEST_WITH_SCOPE_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
@@ skipping 17 matching lines @@
   BuildSettings* build_settings() { return &build_settings_; }
   Settings* settings() { return &settings_; }
   Toolchain* toolchain() { return &toolchain_; }
   Scope* scope() { return &scope_; }
 
   // This buffer accumulates output from any print() commands executed in the
   // context of this test. Note that the implementation of this is not
   // threadsafe so don't write tests that call print from multiple threads.
   std::string& print_output() { return print_output_; }
 
+  // Fills in the tools for the given toolchain with reasonable default values.
+  // The toolchain in this object will be automatically set up with this
+  // function, it is exposed to allow tests to get the same functionality for
+  // other toolchains they make
+  static void SetupToolchain(Toolchain* toolchain);
+
  private:
   void AppendPrintOutput(const std::string& str);
 
   BuildSettings build_settings_;
   Settings settings_;
   Toolchain toolchain_;
   Scope scope_;
 
   std::string print_output_;
 
@@ skipping 22 matching lines @@
 
   std::vector<Token> tokens_;
   scoped_ptr<ParseNode> parsed_;
 
   Err parse_err_;
 
   DISALLOW_COPY_AND_ASSIGN(TestParseInput);
 };
 
 #endif  // TOOLS_GN_TEST_WITH_SCOPE_H_