mainline_system.mk is inherited by not only Pixels but also products
like GSI and sdk_gphone where kernel isn't capable of supporting
updatable APEX.
Stop inheriting updatable_apex.mk from mainline_system.mk and let each
product to decide whether or not to inherit updatable_apex.mk.
Also, TARGET_FLATTEN_APEX is not set to true for GSI as it is the
default setting.
Bug: 132664085
Test: choosecombo 1 aosp_arm64 userdebug; get_build_var
TARGET_FLATTEN_APEX shows true
choosecombo 1 sdk_gphone userdebug; get_build_var TARGET_FLATTEN_APEX
shows true
Change-Id: I3c4e1e4b2bbebd675904d148dd18acb57ecbdfe9
TARGET_FLATTEN_APEX and ro.apex.updatable cannot be independently set.
For a device where updating APEXes is not supported, ro.apex.updatable
should not be set (or set to false) and TARGET_FLATTEN_APEX should be
set to true. For APEX-supporting devices, it is the opposite;
ro.apex.updatable == true and TARGET_FLATTEN_APEX is false (or not set).
To ensure this relationship, TARGET_FLATTEN_APEX is by default set to
true, and overridden to false when updatable_apex.mk is inherited.
Bug: 130623080
Test: choosecombo to Pixels 2 and later; get_build_var
TARGET_FLATTEN_APEX returns false.
choosecombo to the original Pixel and other non-Pixel targets;
get_build_var TARGET_FLATTEN_APEX returns true.
choosecombo to the cuttlefish; get_build_var TARGET_FLATTEN_APEX
returns false
Change-Id: Id73a594dd9838457e68e2793122592c11a84fc83
The product abstracts configs that need to be set to support updating of
APEXes.
Bug: 130418467
Test: m
Test: adb shell getprop ro.apex.updatable in Pixel 2 and 3
Test: adb shell /system/apex/com.android.apex.cts.shim.apex exists.
Change-Id: Idb44388a0cf6338f8b4500a1d0d2762ed59476bf
