releasetools: Really allow removing partitions

- Add hashtree_info to EmptyImage so that BlockDifference.Compute()
can accept EmptyImage() as target image, which is the case when
a partition is removed.

- BlockDifference also checks source_info_dict to determine
whether a partition is dynamic. When a partition is removed,
its name does not appear in target_info_dict.

- Add tests to ensure DynamicPartitionDifference() still works.

Test: DynamicPartitionDifferenceTest
Test: test_blockimgdiff

Change-Id: Iadb1db075f5dc344db6d5ade358c83b01231e443
3 files changed
tree: 63e7e7233009b127b7ae7ae75fcf79e4ef963abb
  1. common/
  2. core/
  3. packaging/
  4. target/
  5. tests/
  6. tools/
  7. .gitignore
  8. buildspec.mk.default
  9. Changes.md
  10. CleanSpec.mk
  11. envsetup.sh
  12. help.sh
  13. navbar.md
  14. OWNERS
  15. README.md
  16. tapasHelp.sh
  17. 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For an outdated reference on Android.mk files, see build-system.html.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.

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