[GN] Add deployment target in generated project.

tools/gn/xcode_writer.h

Index: tools/gn/xcode_writer.h
diff --git a/tools/gn/xcode_writer.h b/tools/gn/xcode_writer.h
index 8c4e3040a0932af290c44a27b57cefa650a5c66f..d618ede2f75b3170819de27b171fc570bee537b2 100644
--- a/tools/gn/xcode_writer.h
+++ b/tools/gn/xcode_writer.h
@@ -28,11 +28,6 @@ class FilePath;
 
 class XcodeWriter {
  public:
-  enum TargetOsType {
-    WRITER_TARGET_OS_IOS,
-    WRITER_TARGET_OS_MACOS,
-  };
-
   // Writes Xcode workspace and project files.
   //
   // |workspace_name| is the optional name of the workspace file name ("all"
@@ -55,6 +50,12 @@ class XcodeWriter {
   XcodeWriter(const std::string& name);
   ~XcodeWriter();
 
+  // Returns the attributes to use for the projects.
+  static bool GetProjectsAttributes(
+      const BuildSettings* build_settings,
+      PBXAttributes* attributes,
+      Err* err);
+
   // Filters the list of targets to only return the targets with artifacts
   // usable from Xcode (mostly application bundles). On failure populate |err|
   // and return false.
@@ -73,8 +74,7 @@ class XcodeWriter {
                              const std::string& config_name,
                              const std::string& root_target,
                              const std::string& ninja_extra_args,
-                             const BuildSettings* build_settings,
-                             TargetOsType target_os);
+                             const BuildSettings* build_settings);
 
   // Generates the "sources.xcodeproj" project that reference all source
   // files to allow Xcode to index them.
@@ -82,8 +82,7 @@ class XcodeWriter {
                             const SourceDir& root_build_dir,
                             const PBXAttributes& attributes,
                             const std::string& source_path,
-                            const std::string& config_name,
-                            TargetOsType target_os);
+                            const std::string& config_name);
 
   bool WriteFiles(const BuildSettings* build_settings, Err* err);
   bool WriteProjectFile(const BuildSettings* build_settings,