[GN] Add support for generating Xcode projects.

tools/gn/bundle_data.h

 // Copyright 2016 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_BUNDLE_DATA_H_
 #define TOOLS_GN_BUNDLE_DATA_H_
 
 #include <string>
 #include <vector>
 
@@ skipping 80 matching lines @@
 
   SourceDir& resources_dir() { return resources_dir_; }
   const SourceDir& resources_dir() const { return resources_dir_; }
 
   SourceDir& executable_dir() { return executable_dir_; }
   const SourceDir& executable_dir() const { return executable_dir_; }
 
   SourceDir& plugins_dir() { return plugins_dir_; }
   const SourceDir& plugins_dir() const { return plugins_dir_; }
 
+  std::string& product_type() { return product_type_; }
+  const std::string& product_type() const { return product_type_; }
+
   // Recursive collection of all bundle_data that the target depends on.
   const UniqueTargets& bundle_deps() const { return bundle_deps_; }
 
  private:
   SourceFiles asset_catalog_sources_;
   BundleFileRules file_rules_;
   UniqueTargets bundle_deps_;
 
   // All those values are subdirectories relative to root_build_dir, and apart
   // from root_dir, they are either equal to root_dir_ or subdirectories of it.
   SourceDir root_dir_;
   SourceDir resources_dir_;
   SourceDir executable_dir_;
   SourceDir plugins_dir_;
+
+  // This is the target type as known to Xcode. This is only used to generate
+  // the Xcode project file when using --ide=xcode.
+  std::string product_type_;
+
+  DISALLOW_COPY_AND_ASSIGN(BundleData);
 };
 
 #endif  // TOOLS_GN_BUNDLE_DATA_H_