Add support for data deps.

tools/gn/variables.h

Index: tools/gn/variables.h
diff --git a/tools/gn/variables.h b/tools/gn/variables.h
new file mode 100644
index 0000000000000000000000000000000000000000..2d461000cf1fbbd491ec523ab92954318b5c1e1f
--- /dev/null
+++ b/tools/gn/variables.h
@@ -0,0 +1,122 @@
+// 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_VARIABLES_H_
+#define TOOLS_GN_VARIABLES_H_
+
+#include <map>
+
+#include "base/strings/string_piece.h"
+
+namespace variables {
+
+// Builtin vars ----------------------------------------------------------------
+
+extern const char kCurrentToolchain[];
+extern const char kCurrentToolchain_HelpShort[];
+extern const char kCurrentToolchain_Help[];
+
+extern const char kDefaultToolchain[];
+extern const char kDefaultToolchain_HelpShort[];
+extern const char kDefaultToolchain_Help[];
+
+extern const char kPythonPath[];
+extern const char kPythonPath_HelpShort[];
+extern const char kPythonPath_Help[];
+
+extern const char kRelativeRootGenDir[];
+extern const char kRelativeRootGenDir_HelpShort[];
+extern const char kRelativeRootGenDir_Help[];
+
+extern const char kRelativeRootOutputDir[];
+extern const char kRelativeRootOutputDir_HelpShort[];
+extern const char kRelativeRootOutputDir_Help[];
+
+extern const char kRelativeTargetGenDir[];
+extern const char kRelativeTargetGenDir_HelpShort[];
+extern const char kRelativeTargetGenDir_Help[];
+
+extern const char kRelativeTargetOutputDir[];
+extern const char kRelativeTargetOutputDir_HelpShort[];
+extern const char kRelativeTargetOutputDir_Help[];
+
+// Target vars -----------------------------------------------------------------
+
+extern const char kAllDependentConfigs[];
+extern const char kAllDependentConfigs_HelpShort[];
+extern const char kAllDependentConfigs_Help[];
+
+extern const char kCflags[];
+extern const char kCflags_HelpShort[];
+extern const char* kCflags_Help;
+
+extern const char kCflagsC[];
+extern const char kCflagsC_HelpShort[];
+extern const char* kCflagsC_Help;
+
+extern const char kCflagsCC[];
+extern const char kCflagsCC_HelpShort[];
+extern const char* kCflagsCC_Help;
+
+extern const char kCflagsObjC[];
+extern const char kCflagsObjC_HelpShort[];
+extern const char* kCflagsObjC_Help;
+
+extern const char kCflagsObjCC[];
+extern const char kCflagsObjCC_HelpShort[];
+extern const char* kCflagsObjCC_Help;
+
+extern const char kConfigs[];
+extern const char kConfigs_HelpShort[];
+extern const char kConfigs_Help[];
+
+extern const char kDatadeps[];
+extern const char kDatadeps_HelpShort[];
+extern const char kDatadeps_Help[];
+
+extern const char kDefines[];
+extern const char kDefines_HelpShort[];
+extern const char kDefines_Help[];
+
+extern const char kDeps[];
+extern const char kDeps_HelpShort[];
+extern const char kDeps_Help[];
+
+extern const char kDirectDependentConfigs[];
+extern const char kDirectDependentConfigs_HelpShort[];
+extern const char kDirectDependentConfigs_Help[];
+
+extern const char kLdflags[];
+extern const char kLdflags_HelpShort[];
+extern const char kLdflags_Help[];
+
+extern const char kSources[];
+extern const char kSources_HelpShort[];
+extern const char kSources_Help[];
+
+
+// -----------------------------------------------------------------------------
+
+struct VariableInfo {
+  VariableInfo();
+  VariableInfo(const char* in_help_short,
+               const char* in_help);
+
+  const char* help_short;
+  const char* help;
+};
+
+typedef std::map<base::StringPiece, VariableInfo> VariableInfoMap;
+
+// Returns the built-in readonly variables.
+// Note: this is used only for help so this getter is not threadsafe.
+const VariableInfoMap& GetBuiltinVariables();
+
+// Returns the variables used by target generators.
+// Note: this is used only for help so this getter is not threadsafe.
+const VariableInfoMap& GetTargetVariables();
+
+}  // namespace variables
+
+#endif  // TOOLS_GN_VARIABLES_H_