Revert of Use a stamp file when symlinking in GN work around mtime issues

build/symlink.gni

Index: build/symlink.gni
diff --git a/build/symlink.gni b/build/symlink.gni
index 174278cbe601664822623db61c8c2bc40223ee82..95a498de1b48e0123435e649124f33668d066a7e 100644
--- a/build/symlink.gni
+++ b/build/symlink.gni
@@ -14,17 +14,11 @@
                              "testonly",
                              "visibility",
                            ])
-
-    # Can't use the symlink itself as an output since ninja does not properly
-    # process the symlink's mtime.
-    # https://github.com/ninja-build/ninja/issues/1186
     outputs = [
-      "$target_gen_dir/$target_name.stamp",
+      invoker.output,
     ]
     script = "//build/symlink.py"
     args = [
-      "--touch",
-      rebase_path(outputs[0], root_build_dir),
       "-f",
       rebase_path(invoker.source, get_path_info(invoker.output, "dir")),
       rebase_path(invoker.output, root_build_dir),