Drop HOST_CROSS_OS special-case in source vs prebuilt mainline selection

We currently do not have many products that cross compile to
linux_bionic, and none of them use google apexes.

One exception is `mainline_sdk` product, but this product exclusively
builds using the `mainline` release config. This release config contains
the necessary RELEASE_APEX_CONTRIBUTIONS_* to provide sources during the
build, so we do not need this additional special-case here

Bug: 308188056
Test: lunch trout_arm64-next-userdebug && get_build_var
PRODUCT_PACKAGES; verified that google apexes do not appear there before
this CL, effectively making this CL a no-op for that product

Change-Id: Ibfdc742b6ae01242be22a3d3f6bb3c0cf551705f
1 file changed
tree: d606d40a315a4f42ad20bd4b690e860368bbb051
  1. ci/
  2. common/
  3. core/
  4. packaging/
  5. target/
  6. teams/
  7. tests/
  8. tools/
  9. .gitignore
  10. banchanHelp.sh
  11. buildspec.mk.default
  12. Changes.md
  13. CleanSpec.mk
  14. cogsetup.sh
  15. Deprecation.md
  16. envsetup.sh
  17. help.sh
  18. METADATA
  19. navbar.md
  20. OWNERS
  21. PREUPLOAD.cfg
  22. rbesetup.sh
  23. README.md
  24. shell_utils.sh
  25. tapasHelp.sh
  26. Usage.txt
README.md

Android Make Build System

This is the Makefile-based portion of the Android Build System.

For documentation on how to run a build, see Usage.txt

For a list of behavioral changes useful for Android.mk writers see Changes.md

For an outdated reference on Android.mk files, see build-system.html. Our Android.mk files look similar, but are entirely different from the Android.mk files used by the NDK build system. When searching for documentation elsewhere, ensure that it is for the platform build system -- most are not.

This Makefile-based system is in the process of being replaced with Soong, a new build system written in Go. During the transition, all of these makefiles are read by Kati, and generate a ninja file instead of being executed directly. That's combined with a ninja file read by Soong so that the build graph of the two systems can be combined and run as one.