Rename FastArray{Push,Pop,Shift,Slice} to
ArrayPrototype{Push,Pop,Shift,Slice}.

Bug: v8:7127, v8:7204, v8:7205
Change-Id: I409fcb4b088f1acece7c6520690f419cad36e78c
Reviewed-on: https://chromium-review.googlesource.com/846982Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Commit-Queue: Sigurd Schneider <sigurds@chromium.org>
Cr-Commit-Position: refs/heads/master@{#50334}