The nested_array.*sampler2D_* tests can pass on Mali with disabled
forceOldRewriteStructSamplers.

Test: dEQP-GLES31.functional.uniform_location.nested_array.*sampler2D_*
Bug: angleproject:2703
Change-Id: I34368d6ce14b81e873e2a3d60a73da4a8a866884
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2377627
Commit-Queue: Amy Liu <Amy.Liu@arm.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@chromium.org>