[Zucchini] Simplify Abs32GapFinder and Rel32Finder.

Previously, using Abs32GapFinder / Rel32Finder to visit gaps / rel32
references involves calling a getter that returns an optional<> value
whose emptiness indicates end of iteration. The code to use this looks
like:

  for (auto value = finder.GetNext(); value; value = finder.GetNext()) {
    ...
  }

This CL abandons optional<> usage and caches the results in Finders,
thereby removing repetition in iteration code:

  while (finder.FindNext() {
    auto value = finder.GetValue();
    ...
  }

Additional changes:
* Incorporate AddressTranslator into Rel32Finder to offload translation
  work from callers.
* Add tests to integrate Abs32GapFinder with Rel32Finder.
  * Stylize test data to better show overlap between abs32 references
    with disassembled test data.

Bug: 918867
Change-Id: Id044b67550f81c3f46ab383c5b6200906f56ca4e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2918113
Reviewed-by: Etienne Pierre-Doray <etiennep@chromium.org>
Commit-Queue: Samuel Huang <huangs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#888049}
NOKEYCHECK=True
GitOrigin-RevId: 89023e1c511e599e6aeaf0b8d80e3efa2e730b5b

0 files changed, 0 insertions, 0 deletions