Add overlay folders for swe channels

Change-Id: I6c58662ccc2f508106426d7c6ee6885ffe32879c
diff --git a/swe_android_browser.gypi b/swe_android_browser.gypi
index cb19eb7..40795cc 100644
--- a/swe_android_browser.gypi
+++ b/swe_android_browser.gypi
@@ -33,6 +33,8 @@
         'additional_input_paths': [
           '<@(chrome_android_pak_output_resources)',
         ],
+        'res_extra_dirs': [ '<@(swe_extra_res_dirs)',
+                          ],
         'override_package_name': '<!(python <(swe_py_config) \
                                      -i <(browser_config_path) \
                                      -c PACKAGE_NAME)',