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The ui::Compositor recycling path involves resizing the surface to be
0x0 and ignoring in-flight swaps. This is delicate logic that probably
doesn't work with SkiaRenderer. There are two DCHECKs that are hit when
this is enabled that aren't when it isn't.

ui::Compositor recycling was designed to work around poor design
decision that dates back at least 8 years. This is the design where the
GLRenderer and all its state (shader cache, etc), is a per-compositor
object, and there are compositors for every tab (historically) and
every window (currently).

A concrete example of where this causes problems: If the user presses a
key in the omnibox, then before any content can be rendered, a whole
bunch of shaders have to be compiled, because it's a new compositor.
If the GLRenderer were a global object shared by all compositors, this
wouldn't happen.

With SkiaRenderer, we happen to have sort-of solved this problem, by
moving all of the GLRenderer state (DirectRenderer state, to be more
accurate) into a single GrContext that happens to be shared
between all compositors.

So, rather than try to understand exactly how the delicate dance of
ui::Compositor recycling breaks on SkiaRenderer, just disable it.

Bug: 1135663, 1135399, 1135386
Change-Id: I0d5bf93aaf4584ef26af0e38da40deec0ef9bb16
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2454089Reviewed-by: Peng Huang <penghuang@chromium.org>
Commit-Queue: ccameron <ccameron@chromium.org>
Cr-Commit-Position: refs/heads/master@{#814515}