Store BundleData paths as SourceDirs rather than strings.

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>
 
 #include "tools/gn/bundle_file_rule.h"
+#include "tools/gn/source_dir.h"
 #include "tools/gn/unique_vector.h"
 
 class OutputFile;
 class SourceFile;
 class Settings;
 class Target;
 
 // Returns true if |source| correspond to the path of a file in an asset
 // catalog. If defined |asset_catalog| is set to its path.
 //
@@ skipping 56 matching lines @@
 
   // Returns the list of inputs for the compilation of the asset catalog.
   SourceFiles& asset_catalog_sources() { return asset_catalog_sources_; }
   const SourceFiles& asset_catalog_sources() const {
     return asset_catalog_sources_;
   }
 
   BundleFileRules& file_rules() { return file_rules_; }
   const BundleFileRules& file_rules() const { return file_rules_; }
 
-  std::string& root_dir() { return root_dir_; }
-  const std::string& root_dir() const { return root_dir_; }
+  SourceDir& root_dir() { return root_dir_; }
+  const SourceDir& root_dir() const { return root_dir_; }
 
-  std::string& resources_dir() { return resources_dir_; }
-  const std::string& resources_dir() const { return resources_dir_; }
+  SourceDir& resources_dir() { return resources_dir_; }
+  const SourceDir& resources_dir() const { return resources_dir_; }
 
-  std::string& executable_dir() { return executable_dir_; }
-  const std::string& executable_dir() const { return executable_dir_; }
+  SourceDir& executable_dir() { return executable_dir_; }
+  const SourceDir& executable_dir() const { return executable_dir_; }
 
-  std::string& plugins_dir() { return plugins_dir_; }
-  const std::string& plugins_dir() const { return plugins_dir_; }
+  SourceDir& plugins_dir() { return plugins_dir_; }
+  const SourceDir& plugins_dir() const { return plugins_dir_; }
 
   // 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.
-  std::string root_dir_;
-  std::string resources_dir_;
-  std::string executable_dir_;
-  std::string plugins_dir_;
+  SourceDir root_dir_;
+  SourceDir resources_dir_;
+  SourceDir executable_dir_;
+  SourceDir plugins_dir_;
 };
 
 #endif  // TOOLS_GN_BUNDLE_DATA_H_