Run cquery using an expression
Passing multiple targets to cquery causes an error. Paste:
https://paste.googleplex.com/5320993747763200. Fix this by creating an
algebraic union expression.
As a trivial example, instead of the following
```
c = //bionic/libc/libc.contribution //bionic/libm/libm.contribution
build/bazel/bin/bazel --config=android --config=api_bp2build cquery $c
```
Run it as
```
c = //bionic/libc/libc.contribution union //bionic/libm/libm.contribution
build/bazel/bin/bazel --config=android --config=api_bp2build cquery $c
```
Also skip bp2build in the cquery call, since we just ran bp2build to
build the metadata files. This should be a no-op anyways, but doing that
check takes some time (~2s).
Test: multitree_build locally
Change-Id: Ie551a40f210d07ac6f0f9895bd66f0408fc1b8cd
1 file changed
