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The most common transform used in rendering are simple transforms,
such as translation and scaling. This patch is aimed to optimize the
usage of these simple transforms.

We used to transform every draw quad to the target space and verify
that if the draw quad is behind a occlusion region or not. Since these
simple transforms are invertible, we can transform the occlusion
region from the target space to the coordinate space so that we can
do the verification without applying transform on draw quad. The
traversal speed is increased by 8 times as shown here:
https://docs.google.com/document/d/1gM4h1ca2jDWdXbYa9yjC53m0sJzaT9skqbPGnfDsdyI/edit#heading=h.7y9syhsnunpw

Before:
98.26% viz::Display::RemoveOverdrawQuads(CompositorFrame)
  95.58% viz::Display::RemoveOverdrawQuads(CompositorFrame)
  53.17% cc::MathUtil::MapEnclosingClippedRect(gfx::Transform, Rect)
  9.36% cc::ListContainer::viz::DrawQuad::Iterator
  9.07% cc::ListContainer::viz::SharedQuadState::end
  6.77% cc::MathUtil::MapEnclosedRectWith2dAxisAlignedTransform(gfx::Transform, Rect)
  5.20% cc::SimpleEnclosedRegion::Union(gfx::Rect)
  4.46% cc::SimpleEnclosedRegion::Contains(gfx::Rect)
  2.28% cc::ListContainerHelper::PositionInCharAllocator

After applying this patch,
https://chromium-review.googlesource.com/c/chromium/src/+/783799
and https://chromium-review.googlesource.com/c/chromium/src/+/782063:
97.37% viz::Display::RemoveOverdrawQuads(CompositorFrame)
  1.23% cc::LapTimer::NextLap()
  0.48% cc::ListContainer::viz::SharedQuadState::ReverseIterator
  0.21% gfx::Rect::IsEmpty()
  0.17% gfx::Transform(SkMatrix44)
  0.09% cc::LapTimer::HasTimeLimitExpired()
  0.08% cc::ListContainerHelper::PositionInCharAllocator


Bug: 
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel
Change-Id: Iee7fb16e44637489a155101e4cc39e128e45acc4
Reviewed-on: https://chromium-review.googlesource.com/788283
Commit-Queue: Yi Xu <yiyix@chromium.org>
Reviewed-by: danakj <danakj@chromium.org>
Cr-Commit-Position: refs/heads/master@{#521380}