Add link to internal Android debugging instructions

Bug: None
Change-Id: Ia5efcfaf1a165487e4b449eebfa5f42448539d35
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2416455Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#808178}

docs/android_debugging_instructions.md

@@ -4,6 +4,11 @@ for debugging. Here's some tips.
 
 [TOC]
 
+## Instructions for Google Employees
+
+See also
+[go/clankium/06-debugging-clank](https://goto.google.com/clankium/06-debugging-clank).
+
 ## Launching
 You can run the app by using one of the wrappers.