Spring Simplify some redundant code

I find some code to refactor using analysis : * Redundant Collection.addAll() call. It may cause one time array copy. * The code like this.messageBytesToRead >= input.readableByteCount() ? input.readableByteCount() : this.messageBytesToRead; may cause one more time input.readableByteCount() call.

Comment From: zhangt2333

@sbrannen Aha, Thanks for your code review !

Comment From: sbrannen

Thanks for making the requested changes. I plan to merge this after 5.2.4 has been released.

Comment From: sbrannen

This has been merged into master.

Thanks