All the optimizations have now been moved to either the BytecodeGenerator
or the BytecodeArrayWriter/Builder.

BUG=v8:6194

Change-Id: Ie5c5d55e824c94ffb503af376c72bc64ad1f6f81
Reviewed-on: https://chromium-review.googlesource.com/469349
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Michael Achenbach <machenbach@chromium.org>
Cr-Commit-Position: refs/heads/master@{#44564}