Remove the bulk add-renderTasks entry point from the drawing manager

With the addition of the ddlTask this is no longer needed.

Change-Id: I39c60d2bbe3bc335146d51dc0b0ca8a45dc812f2
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/333463
Reviewed-by: Adlai Holler <adlai@google.com>
Commit-Queue: Robert Phillips <robertphillips@google.com>
2 files changed