Add a very basic PIN UI implementation that is shared between lock and settings.

chrome/browser/resources/settings/people_page/pin.css

Index: chrome/browser/resources/settings/people_page/pin.css
diff --git a/tools/android/loading/trace_test/tests/1.css b/chrome/browser/resources/settings/people_page/pin.css
similarity index 75%
copy from tools/android/loading/trace_test/tests/1.css
copy to chrome/browser/resources/settings/people_page/pin.css
index 5ae3598668c348eeb78a00dc5c7655ef5837c1b6..f8afaea12788f5d211741f4ddebf8882c24f25fa 100644
--- a/tools/android/loading/trace_test/tests/1.css
+++ b/chrome/browser/resources/settings/people_page/pin.css
@@ -3,7 +3,4 @@
  * found in the LICENSE file.
  */
 
-.outside {
-    font-family: inline;
-    color: red;
-}
+<include src="../../chromeos/quick_unlock/pin.css">