This reverts commit 0bb42e09.

Reason for revert: https://bugs.chromium.org/p/chromium/issues/detail?id=1026633

Causing failures on Mac bots.

Original change's description:
> Metal: Enable end2end tests.
> 
> Explicitly disabled tests:
> - DifferentStencilMasksTest.DrawWithDifferentMask
> - PointSpritesTest.PointSizeAboveMaxIsClamped
> - WebGL2ReadOutsideFramebufferTest.CopyTexSubImage3D
> 
> Bug: angleproject:2634
> Change-Id: I76ab450c06d0e1be1e7469a8b9c6497684c3ca54
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1906607
> Commit-Queue: Jamie Madill <jmadill@chromium.org>
> Reviewed-by: Jamie Madill <jmadill@chromium.org>
> Reviewed-by: Geoff Lang <geofflang@chromium.org>

TBR=geofflang@chromium.org,jonahr@google.com,jmadill@chromium.org,le.hoang.q@gmail.com

Change-Id: Iaa4264834170a49c274f186d3d74f57714c84b32
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: angleproject:2634
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1926378Reviewed-by: Courtney Goeltzenleuchter <courtneygo@google.com>
Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com>