GN: Use lib.unstripped rather than lib.stripped. Add a toolchain.gni

third_party/cython/rules.gni

Index: third_party/cython/rules.gni
diff --git a/third_party/cython/rules.gni b/third_party/cython/rules.gni
index ea6e0aebf6f4db6ab5bd43bd88f04301de446668..1d702df7de7aabdbe10023ec82304058d1992328 100644
--- a/third_party/cython/rules.gni
+++ b/third_party/cython/rules.gni
@@ -2,6 +2,8 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+import("//build/toolchain/toolchain.gni")
+
 template("python_binary_source_set") {
   # Only available on linux for now.
   assert(is_linux)
@@ -149,7 +151,7 @@ template("python_binary_module") {
     }
 
     sources = [
-      "$root_out_dir/${shared_library_prefix}${shared_library_name}${shared_library_suffix}",
+      "$root_shlib_dir/${shared_library_prefix}${shared_library_name}${shared_library_suffix}",
     ]
     outputs = [
       output,