Add test project for api in library projects.

Also tweak the API a bit.

Change-Id: I6cb10b4d770f9054f269d600d41a24b7e2fdc2e1
diff --git a/.gitignore b/.gitignore
index 8968a13..74cc78a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -8,6 +8,7 @@
 gradle/build
 tests/*/build
 tests/*/build
+tests/api/*/build
 tests/multiproject/*/build
 tests/tictactoe/*/build
 tests/applibtest/*/build