g3: add d850 and d855 to build barriers

Change-Id: I88f16736dab3ba31f57e395cbbf21d5d04875106
g3: use xxhdpi dalvik heap settings

Change-Id: I41eb17a38c6b0acbfd6ab1a0bcfe2a3a17dd736f
g3: add d852 to build barriers

Change-Id: I75cd171c7cde9384355b43f3191584918c41f85d
Merge https://github.com/invisiblek/android_device_lge_g3-common into ice5.0