Flying Does Not Disable Gliding

While gliding in creative mode, if you start flying while gliding, you will remain to glide, just very slowly.

Steps to reproduce:
1. Go in creative mode
2. Get an elytra and equip it
3. Start gliding
4. Immediately start flying

Observed Result:
You should be flying while gliding.

Expected Result:
You should be flying while gliding.