envsetup: add a helper to fix "out/target/common" not being really common

* out/target/common isn't really common, and if you do
  back to back builds for multiple devices, that is noticable.
* Use out/target/common-$device instead, and link the appropriate
  dir to out/target/common every time lunch() is run, if
  ANDROID_FIXUP_COMMON_OUT is set.
* Refer https://groups.google.com/forum/#!topic/android-building/ispbOgzoyg8
  for more info.

Change-Id: I11e7df0e68e2a60ce32576f06397d60fc9465b60
1 file changed
tree: 21014e1831241b4b05f9b9a5223351578a858fbf
  1. build/
  2. charger/
  3. config/
  4. overlay/
  5. prebuilt/
  6. sepolicy/
  7. utils/
  8. Android.mk