A bit of libdex spring cleaning.

Give the UTF-8 parsing/validation code and the debug info decoder
their own files in libdex. Also, moved the random utility
dexRoundUpPower2() so it wasn't in the middle of unrelated stuff
(though maybe it doesn't want to stay in DexFile.c at all).

Change-Id: I115447e49904e2440dd538b1df90616ea95707a9
12 files changed