- Patch #49993 by Sid_M: fixed two minor problems with HTTPGet().

1) There is a race condition created by calling send() before setting the callback function. Admittedly, this race shouldn't be lost, but it's not good practice to bet on winning races in code.

2) Line 55 is redundant. Since the value of bAsync is based on the non/existence of callbackFunction, there is no need to check both variables later.