Add forward_variables_from() and target() to GN

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"
 #include "tools/gn/build_settings.h"
 #include "tools/gn/err.h"
 #include "tools/gn/input_file.h"
 #include "tools/gn/parse_tree.h"
 #include "tools/gn/scope.h"
+#include "tools/gn/scope_per_file_provider.h"
 #include "tools/gn/settings.h"
 #include "tools/gn/target.h"
 #include "tools/gn/token.h"
 #include "tools/gn/toolchain.h"
 #include "tools/gn/value.h"
 
 // A helper class for setting up a Scope that a test can use. It makes a
 // toolchain and sets up all the build state.
 class TestWithScope {
  public:
@@ skipping 26 matching lines @@
   static void SetCommandForTool(const std::string& cmd, Tool* tool);
 
  private:
   void AppendPrintOutput(const std::string& str);
 
   BuildSettings build_settings_;
   Settings settings_;
   Toolchain toolchain_;
   Scope scope_;
 
+  // Supplies the scope with built-in variables like root_out_dir.
+  ScopePerFileProvider scope_progammatic_provider_;
+
   std::string print_output_;
 
   DISALLOW_COPY_AND_ASSIGN(TestWithScope);
 };
 
 // Helper class to treat some string input as a file.
 //
 // Instantiate it with the contents you want, be sure to check for error, and
 // then you can execute the ParseNode or whatever.
 class TestParseInput {
@@ skipping 25 matching lines @@
 // default to public visibility.
 class TestTarget : public Target {
  public:
   TestTarget(TestWithScope& setup,
              const std::string& label_string,
              Target::OutputType type);
   ~TestTarget() override;
 };
 
 #endif  // TOOLS_GN_TEST_WITH_SCOPE_H_