Summary: Wrap further native methods in FileInputStreams
Reviewed-by: chegar, bpb, rriggs
Contributed-by: sunny.chan@gs.com

Summary: Wrap some native methods in Java methods.
Reviewed-by: rriggs

Reviewed-by: alanb, dsamersoff, jbachorik

Summary: Correct the behavior of available() and update related java specs for available() and skip() in InputStream and FileInputStream classes.
Reviewed-by: alanb

Reviewed-by: darcy, weijun