tree c3660b73589784889be77327f4a0e6dfdefc86cf
parent 58b8c86f84ad0bf8fb3bb7dfc259fd1e3ce0dae1
author Ying Wang <wangying@google.com> 1457067441 -0800
committer Ying Wang <wangying@google.com> 1457118117 -0800

Speed up lunch/tapas/etc. shell utility functions.

1. Combined ~10 calls to the make build system to only one.
   We added a phony target "dump-many-vars" to the build system to dump
   "<var>=<value>" pairs. We then store the pairs as shell variables.
   With this cache get_build_var/get_abs_build_var can just return
   the shell variables instead of querying the build system.
2. Prune .git when we search for AndroidProduct.mks.

In internal source tree lunch time was reduced from ~15s to ~1.5s.

Bug: 27429759
Change-Id: I24e88598f6fab598ef26518885fd5e86e71a772d