Write expected length of out arrays to parcel

This makes generated C++ consistent with the Java.

Unfortunately, C++ server authors still need to understand
that if they resize inout/out arrays, this will cause runtime exceptions
for Java clients, which cannot resize their array types.
Addressing this is a much more invasive patch.

Bug: 30836680
Change-Id: I996bfea8383d6207377e7bc545d3d39c21bbe033
Test: integration and unit tests continue to pass
2 files changed