Add AbtChromeExtensionProtocol

Test: build local ABT chrome extension (go/abt-extension) (version in manifest must match
chrome version and winscope URL must point to dev winscope), open a buganizer bug with .zip
and/or <file>.winscope attachments, click on the button "open in winscope".

Fix: b/255966630

Change-Id: Id61114b88ebf59d5f43f6b8a8a74566233a0b8d1
10 files changed