Duplication in Crafting Menu

^{Updated Description by [Mojang] Mega_Spud (Jay Wells):}
Summary:
Items can be easily duplicated in the crafting section, when using the Pocket UI and touch controls.

Steps to Reproduce:

1. Open the survival inventory crafting area
2. Take a stack of items
3. Tap it into the crafting grid
4. Tap the other grid sections one after the other

Observed Results:
All of the crafting grid sections fill up with stacks of items, duplicating them.

Expected Results:
The items shouldn't be duplicated at all.

Screenshots/Videos attached: Yes

Notes:

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Original Description:
When I click an empty slot in the crafting menu then an item that is occupying one of the 4 slots for example Wooden Planks it duplicates for some reason.