* Mark BytecodeOperands and Bytecodes AllStatic.
* Add BytecodeOperands::kOperandScaleCount.
* Add Bytecodes::ReusesExistingHandler in preparation for adding another
  callsite from deserialization.

Bug: v8:6624
Change-Id: Ic8b5d444df5525ef6d14de6931b38afd926b251e
Reviewed-on: https://chromium-review.googlesource.com/738092Reviewed-by: Mythri Alle <mythria@chromium.org>
Commit-Queue: Jakob Gruber <jgruber@chromium.org>
Cr-Commit-Position: refs/heads/master@{#48957}