This patch also changes the visitor of BytecodeArray to use
BytecodeArray::BodyDescriptor.

BUG=chromium:733159

Change-Id: I2ac72c97ec51996b5b100c447b543895180f4f78
Reviewed-on: https://chromium-review.googlesource.com/535674Reviewed-by: Michael Lippautz <mlippautz@chromium.org>
Commit-Queue: Ulan Degenbaev <ulan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45955}