Add a startup benchmark and rudimentary scripts for running benchmarks.

BUG=None
TEST=None
R=abarth@chromium.org

Review URL: https://codereview.chromium.org/724243002
diff --git a/benchmarks/DEPS b/benchmarks/DEPS
new file mode 100644
index 0000000..0669117
--- /dev/null
+++ b/benchmarks/DEPS
@@ -0,0 +1,3 @@
+include_rules = [
+  "+mojo",
+]