Rather than assume success, allow WSI surface implementations to return
a VkResult for getSurfaceCapabilities.

Also, made VkSurfaceKHR::getSurfaceCapabilities pure virtual, and moved
its implementation to a protected static helper named
setCommonSurfaceCapabilities.

Bug: chromium:1174372
Change-Id: I75f5f5a30f786f0675d830e4e2a684a4cbcb149c
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/53048
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Antonio Maiorano <amaiorano@google.com>
Commit-Queue: Antonio Maiorano <amaiorano@google.com>