With MonomorphizeUnsupportedFunctionsInVulkanGLSL and
RewriteArrayOfArrayOfOpaqueUniforms transformations run, it is no longer
possible to encounter array of array of atomic counters, or have any
passed to functions.  As a result, RewriteAtomicCounters is greatly
simplified.  Additionally, it is no longer necessary to pass
binding/offset information for atomic counters around and they can use
constants.  This change removes dependency on the
shaderStorageBufferArrayDynamicIndexing Vulkan feature.

Bug: angleproject:3726
Bug: angleproject:3881
Change-Id: Ia43092a668f60d009eccbbceeed5deaf105a5895
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2633687Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>