Include dist target to build the build metrics for the vendor inner
tree build.
Bug: 241033491
Test: development/multitree/build_vendor.sh -d vsoc_x86_64 \
-p cf_x86_64_phone -r out/dist -i %bid%
Change-Id: I7230fe2ee70eefad5e71cec7d5dc710f74f8c503
To monitor ninja inputs, generate ninja_inputs.pb as build metrics.
This will count the number of input files and required git projects,
with the number of files for each project.
Bug: 241033491
Test: $ cp .repo/manifests/default.xml out/dist/manifest_1.xml
$ development/multitree/build_vendor.sh -d vsoc_x86_64 \
-p cf_x86_64_phone -r out/dist -i 1
Change-Id: Ie185863f1c8fca313baba6135374d509e2d93937
