[Mac/GN] Treat create_bundle as a leaf for `gn desc runtime_deps`.

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 59 matching lines @@
   // any other subpath, this is just the most top-level directory (e.g.,
   // just Bundle.app/).
   //
   // Note that this is a SourceFile instead of a SourceDir. This is because
   // the output of a create_bundle rule is a single logical unit, even though
   // it is really a directory containing many outputs. This allows other
   // targets to treat the bundle as a single unit, rather than a collection
   // of its contents.
   SourceFile GetBundleRootDirOutput(const Settings* settings) const;
 
+  // Performs GetBundleRootDirOutput but returns the result as a directory.
+  SourceDir GetBundleRootDirOutputAsDir(const Settings* settings) const;
+
   // 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_; }
 
   SourceDir& root_dir() { return root_dir_; }
@@ skipping 27 matching lines @@
   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_