Assert that MicroSpinLock is a POD type
Assert that MicroSpinLock is a POD type

Summary: Because if it's not, all hell will break lose (apparently).

Reviewed By: meyering

Differential Revision: D3373061

fbshipit-source-id: f08a863d1bacadeeff9d9cea041f399f136cfc74

facebook/folly,mqeizi/folly,mqeizi/folly,floxard/folly,rklabs/folly,mqeizi/folly,rklabs/folly,charsyam/folly,Orvid/folly,Orvid/folly,charsyam/folly,mqeizi/folly,facebook/folly,floxard/folly,Orvid/folly,rklabs/folly,rklabs/folly,brunomorishita/folly,brunomorishita/folly,Orvid/folly,mqeizi/folly,rklabs/folly,brunomorishita/folly,charsyam/folly,facebook/folly,facebook/folly,charsyam/folly,facebook/folly,floxard/folly,brunomorishita/folly,floxard/folly,brunomorishita/folly,Orvid/folly,floxard/folly