Work around a Java 1.8.0_11 -> 1.8.0_20 regression.

Providing the full function prototype allows this to typecheck - the
inference broke somewhere between the _11 and _20 patchlevel.

@shbonita please try this.

Signed-off-by: Ricky Elrod <ricky@elrod.me>
Merge branch 'fix-trampoline-jdk-regression'
Document Windows a bit more.

Signed-off-by: Ricky Elrod <ricky@elrod.me>