Construct Firebase SDK instances in a function
Construct Firebase SDK instances in a function

The client still holds on to singletons but they are constructed in a
function, thus making it possible to construct a separate instance if
need be.

jwang1919/popcode,outoftime/learnpad,jwang1919/popcode,outoftime/learnpad,jwang1919/popcode,popcodeorg/popcode,popcodeorg/popcode,popcodeorg/popcode,jwang1919/popcode,popcodeorg/popcode