Add '--dev' and '--debug' options to build_chromeos.py.

'--dev' option builds a writable and bigger chromeos image.  In
addition, '--debug' option builds chromeos-chrome (the browser) with
'-g -O0' while keep everything else unchanged. Notice, '--debug' turns
on '--dev' automatically.

PRESUBMIT=passed
BUG=None
R=llozano,asharif
CC=bjanakiraman,cmtice,yunlian,carrot
APPROVED=yunlian
OCL=65775-p2
RCL=65916-p2
RDATE=2013/02/15 16:20:46
TEST=./build_chromeos.py --chromeos_root=/usr/local/google/home/shenhan/ssd/live --rebuild --debug --board=daisy |& tee ~/log


P4 change: 42807708
3 files changed
tree: f65e53b07dee58658e5d58f6d55277c715bb0dfd
  1. .git5_specs/
  2. v14/