Ömer Sinan Ağacan authored Mar 22, 2019 and Marge Bot committed Mar 27, 2019

- `emitCopySmallArray` now checks size before generating code and
  doesn't generate any code when size is 0. `emitCopyArray` already does
  this so this makes small/large array cases the same in argument
  checking.

- In both `emitCopySmallArray` and `emitCopyArray` read the `dflags`
  after checking the argument.