D3D11 cannot allow the same (sub)-resource bound as both
a SRV and an UAV at the same time. If render pipline and
compute pipeline access the same texture, must unset
conflicting SRVs and UAVs before drawing and dispatching
on D3D backend. Currently, these cases could not pass
on D3D11 backend.

Bug: angleproject:3152
TEST=angle_end2end_tests.ComputeShaderTest.*

Change-Id: I3ed19d7586625aac7fe9f46f86341d136d148019
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1578131Reviewed-by: Jiajia Qin <jiajia.qin@intel.com>
Reviewed-by: Geoff Lang <geofflang@chromium.org>
Commit-Queue: Xinghua Cao <xinghua.cao@intel.com>