The Vulkan device's robustBufferAccess feature determines whether
accesses to buffers must be bounds-checked against the range of the
buffer descriptor.

The spec states that "Some features, such as robustBufferAccess, may
incur a run-time performance cost. Application writers should carefully
consider the implications of enabling all supported features."
Hence in many cases applications will leave the feature disabled to
ensure maximum performance.

Bug: b/131224163
Change-Id: I69e150d5043f0118db8a4b2751b24b5d87bccd75
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/33389
Presubmit-Ready: Nicolas Capens <nicolascapens@google.com>
Tested-by: Nicolas Capens <nicolascapens@google.com>
Kokoro-Presubmit: kokoro <noreply+kokoro@google.com>
Reviewed-by: Chris Forbes <chrisforbes@google.com>
Reviewed-by: Ben Clayton <bclayton@google.com>