Add core-lambda-stubs to default classpath for target libs compiling using javac

In order to compile lambda code javac requires various invokedynamic-
related classes to be present. This change adds stubs needed for
javac to compile lambdas.

Bug: 27475234
Bug: 26753820
Bug: 26604040
Change-Id: Ifc79eebabfc6b64c0daf6b9ca236d1967a45a735