Merge "vulkan: fix crash when only non-global layers are enabled" into nyc-dev am: a101f6a446
am: 95e76d6b82

* commit '95e76d6b820adb487a22dc878a28f09bdffa5fa7':
  vulkan: fix crash when only non-global layers are enabled

Change-Id: I36b3620c2c774c64aae8e695a2a9d47daad91f0f