gwt-dev dependencies were moved from external constant to maven_jar()
exported_deps dependency in I54df92daf. As the consequence, maven_jar
makes from it java_library instead of prebuil_jar. As the consequence
java_library without sources and resources doesn't expose output jar.
This broke java_doc() rule in gwtui-api that makes use of $(location)
macro. This macros is failing on libraries without own output jar.
To rectify it, expose intermediate prebuilt_jar from maven_jar() rule
with the same visibility scope as the final artifact. Now it can be
used in java_doc() as it exposes output jar and exported_deps aren't
needed in this context.
Change-Id: I6168fda0aba8827063958f80c6e2828b0a6941f8
1da31b3520