Case statements have a list of statements associated with them, but are
not blocks, and were hence not fixed-up correctly for code coverage.
This CL also applies the fix-up to the "body" of case statements,
in this way removing ranges reported as uncovered between the final
break/return in a case and the next case (or end of function).

Drive-by: Add optional pretty printing to code coverage test results.

Change-Id: I5f4002d4e17b7253ed516d99f7c389ab2264be10
Bug: v8:9705
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1798426Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Jakob Gruber <jgruber@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63719}