tree f7deb05bd98bca392ab26fd631bfbdf56265239e
parent 4aa75ca244ef7d0150978af626c0478fa784e93d
author Dan Willemsen <dwillemsen@google.com> 1475104750 -0700
committer Dan Willemsen <dwillemsen@google.com> 1475109537 -0700

Parse genrule's cmd property

Instead of just passing this to ninja, use os.Expand to parse the
variable substitutions. While we're here, define a new "genDir" variable
that is the root of this module's generated directory.

Bug: 31742855
Test: Ensure invalid variables cause error
Test: Inspect commands in build.ninja
Change-Id: Iff6d0499ab57367669e73df52ab7c647358da13b