[GN] Add support for generating Xcode projects.

tools/gn/commands.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_COMMANDS_H_
 #define TOOLS_GN_COMMANDS_H_
 
 #include <map>
 #include <set>
 #include <string>
@@ skipping 122 matching lines @@
                         bool force_check);
 
 // Filters the given list of targets by the given pattern list.
 void FilterTargetsByPatterns(const std::vector<const Target*>& input,
                              const std::vector<LabelPattern>& filter,
                              std::vector<const Target*>* output);
 void FilterTargetsByPatterns(const std::vector<const Target*>& input,
                              const std::vector<LabelPattern>& filter,
                              UniqueVector<const Target*>* output);
 
+// Builds a list of pattern from a semicolon-separated list of labels.
+bool FilterPatternsFromString(const BuildSettings* build_settings,
+                              const std::string& label_list_string,
+                              std::vector<LabelPattern>* filters,
+                              Err* err);
+
 // These are the documentation strings for the command-line flags used by
 // FilterAndPrintTargets. Commands that call that function should incorporate
 // these into their help.
 #define TARGET_PRINTING_MODE_COMMAND_LINE_HELP \
     "  --as=(buildfile|label|output)\n"\
     "      How to print targets.\n"\
     "\n"\
     "      buildfile\n"\
     "          Prints the build files where the given target was declared as\n"\
     "          file names.\n"\
@@ skipping 22 matching lines @@
 void FilterAndPrintTargets(bool indent, std::vector<const Target*>* targets);
 void FilterAndPrintTargetSet(bool indent,
                              const std::set<const Target*>& targets);
 
 // Extra help from command_check.cc
 extern const char kNoGnCheck_Help[];
 
 }  // namespace commands
 
 #endif  // TOOLS_GN_COMMANDS_H_