Add external physical display emulation

Use a system property, hwservicemanager.external.displays, to configure
external physical displays. Serveral displays can be specified with
comma (,) as separator, each display has the following info:
    physicalId,width,height,dpi,flags
For example, following specifies 2 displays:
PRODUCT_PRODUCT_PROPERTIES += \
    hwservicemanager.external.displays=1,1200,800,120,0,2,1200,800,120,0

Test: manual
Change-Id: I4cc5b20226333971bfd0cafde743ed7b4d2232b0
2 files changed