This CL is to make the function collapse-pairs(), which is applied to
lists of "property=value" pairs, allow empty properties (i.e. lines of
the form "empty.prop=").
Currently, the function only allows empty properties at the end (see
https://android-review.googlesource.com/c/platform/build/+/722908).
So empty properties in the middle result in broken property files (e.g.
"a=b c= d=e" is transformed to "a=b c=d=e", in which the property "c",
which originally has no value, is interpreted as having the value "d=e",
whereas the property "d", which originally has the value "e", is missing
from the resulting property file).
This CL revises the function so as to keep empty properties in the
middle as is (e.g. it returns "a=b c= d=e" for the above example), while
preserving the behavior for well-formed lists like "a=b c= d e = f".
Bug: 152379493
Test: make
Change-Id: I35faeaedc3bc42e56e01201baf7ea6805a610439
In preparation for setting up another Kati stage, move some common
settings and tools into a common folder. This way it's a bit easier to
see that they're safe to use, and that they shouldn't depend on anything
outside of the common folder.
Bug: 117463001
Test: build-aosp_arm.ninja is the same before and after
Change-Id: Ief4b75a4dbe45b73ffd03bf32c60695c816d979d
