Unzip apk in $(genDir) instead of inside source tree

Android source tree will eventually be made ReadOnly with /tmp and /out
as ReadWrite directories
This CL will ensure that the file extracted during the test will be written to
the sandbox dir $(genDir) instead of $TOP
Formatting changes are due to bpfmt

Bug: 174726238
Test: Built a target in git_master in a RO source tree
1. Before CL, we get this error "error:  cannot create resources.arsc
        Read-only file system"
2. After CL, the above error is fixed

Change-Id: I012284a5835603c54bc2a8bde585a01a4325c43a