Fix sampler2DViewOf3D.

Author: squidbus

MoltenVK/MoltenVK/GPUObjects/MVKDevice.mm

@@ -596,10 +596,7 @@
 				if (getMVKConfig().useMTLHeap) {
 					auto* extFeatures = (VkPhysicalDeviceImage2DViewOf3DFeaturesEXT*)next;
 					extFeatures->image2DViewOf3D = true;
-
-					// TODO (ncesario-lunarg) Related CTS tests (e.g., dEQP-VK.pipeline.monolithic.image_2d_view_3d_image.compute.sampler.mip0_layer0)
-					// are failing with this enabled.
-					extFeatures->sampler2DViewOf3D = false;
+					extFeatures->sampler2DViewOf3D = true;
 				}
 				break;
 			}

MoltenVK/MoltenVK/GPUObjects/MVKImage.mm

@@ -1112,7 +1112,9 @@ static MTLRegion getMTLRegion(const ImgRgn& imgRgn) {
 
 	// Metal before 3.0 doesn't support 3D compressed textures, so we'll
 	// decompress the texture ourselves, and we need to be able to write to it.
-	bool makeWritable = MVK_MACOS && _is3DCompressed;
+	// Additionally, the ability to create 2D view over 3D image is dependent
+	// on the write capability to work correctly.
+	bool makeWritable = (MVK_MACOS && _is3DCompressed) || _is2DViewOn3DImageCompatible;
 	if (makeWritable) {
 		mvkEnableFlags(mtlUsage, MTLTextureUsageShaderWrite);
 	}