Setting LOCAL_CERTIFICATE to "EXTERNAL" now marks an apk (either a
prebuilt or otherwise) as needing the default test key within the
system, but one that should be signed after the target_files is
produced but before sign_target_files_apks does the rest of the
signing. (We use this to ship apps on the system that are signed by
third parties, like Facebook.)
Require people who check in new prebuilts to decide what keys they
should be signed with, rather than having a fire drill every time we
go to sign a build and discover new prebuilts.
If a prebuilt specifies a LOCAL_CERTIFICATE, stick it in the
PACKAGES.* collection so that the predexopt process can work on the
file (which only works if the new .apk can be signed).
Change things so that when $(LOCAL_PREBUILT_STRIP_COMMENTS) is
nonempty, we copy the source file using sed to strip out all the "#
line"-style comments and blank lines, saving considerable system image
space in the case of some wifi configurations.
Bug: 2036961
