Add a special queue to {CompilationUnitQueues} to handle big functions
specially. They are organized in a priority queue (ordered by their
body size), and all threads check this queue first, before executing
the tasks from their own queue. In some benchmarks, this shortens
overall compilation time by 10-20 percent.

R=ahaas@chromium.org

Bug: v8:8916, chromium:950493
Change-Id: I45f36a05304e2f1c4f3ce6b8821ddd4bd08fbba3
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1622122Reviewed-by: Andreas Haas <ahaas@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#61746}