[BUG] Validation layers don't allow null swapchains in xrGetRecommendedLayerResolutionMETA .

[Beyley]

Spec of XR_META_recommended_layer_resolution states "XrRecommendedLayerResolutionGetInfoMETA::layer may contain XR_NULL_HANDLE in place of valid XrSwapchain handle(s) for this function only, to obtain a recommended resolution resolution for the purpose of allocating a swapchain.", however if you attempt to do this, the validation layers will throw an error

error(xr_debug_messenger): [VALIDATION] xrGetRecommendedLayerResolutionMETA, VUID-XrSwapchainSubImage-swapchain-parameter, "Invalid XrSwapchain handle "swapchain" 0x0000000000000000"
error(xr_debug_messenger): [VALIDATION] xrGetRecommendedLayerResolutionMETA, VUID-XrCompositionLayerProjectionView-subImage-parameter, "Structure XrCompositionLayerProjectionView member subImage is invalid"
error(xr_debug_messenger): [VALIDATION] xrGetRecommendedLayerResolutionMETA, VUID-XrCompositionLayerProjection-views-parameter, "Structure XrCompositionLayerProjection member views is invalid"
error(xr_debug_messenger): [VALIDATION] xrGetRecommendedLayerResolutionMETA, VUID-XrRecommendedLayerResolutionGetInfoMETA-layer-parameter, "Structure XrRecommendedLayerResolutionGetInfoMETA member layer is invalid"
error(xr_debug_messenger): [VALIDATION] xrGetRecommendedLayerResolutionMETA, VUID-xrGetRecommendedLayerResolutionMETA-info-parameter, "Command xrGetRecommendedLayerResolutionMETA param info is invalid"

[rpavlik]

Ah, I remember reviewing this extension, that is a tricky exception to verify in generated code. I'll ping somebody.