No need to go through the list when you just want the size
No need to go through the list when you just want the size

Summary: cb is an unused variable, and i got error in android. It seems like we don't need to go through the list to increase count.

Differential Revision: D3622772

fbshipit-source-id: fe1f81a1fcad5bacad052e14b7b0b370beb3f3e5

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