This CL adds navigation support for labels in "goto" statements.
Similar to labels listed in the "otherwise" clause of call expression,
definitions of such a label can be found in two places:
  - The signature of the current macro.
  - A label block of a "try" statement that surrounds the "goto".

R=sigurds@chromium.org

Bug: v8:8880
Change-Id: I6c5ebea0b0f80b1882e6672bbb0f45196a7201ba
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1594433
Commit-Queue: Simon Zünd <szuend@chromium.org>
Reviewed-by: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61229}