Using ChannelBuffer for int8[] types

[jubeira]

I noticed that the changes in #65, messages with int8[] fields are converted to byte[] datatypes in Java messages, but all the message artifacts in rosjava_mvn_repo and the code in android_core and so on is still using ChannelBuffer for these cases.

Steps to reproduce: build rosjava ws from source, source the environment, and build android_core from scratch using catkin. catkin will use the generated message artifacts in the first step instead of using the artifacts in rosjava_mvn_repo, and the build will break when trying to use getData from messages containing byte[]. Error copied below:

src/org/ros/android/view/visualization/layer/CompressedOccupancyGridLayer.java:94: error: incompatible types: byte[] cannot be converted to ChannelBuffer
    ChannelBuffer buffer = message.getData();

I'm not saying that using byte[] is wrong, but it breaks the API for messages using this type of objects and therefore all the code using these messages.

This PR reverts the changes in #65 and attempts to fix the test by using ChannelBuffer instead of byte[] in RawMessage interface. I'm not 100% sure whether we should support byte[] in the set method.

Comments on this are welcome.

[drigz]

Thanks and sorry for the breakage! How much work do you think it would be to run that build with catkin in Travis to catch breakages like this in future?

[jubeira]

Thanks for the review @drigz!

I think it is doable, but first it would be good to restore the failing tests. I'm a bit packed right now and I'll be OOO for most of October, so it'll be a bit complicated for me to do it in the near future.

Besides that, I don't have admin permissions for rosjava organization, so I can't setup a CI platform to work with these repos. Maybe I can do it in my fork and then port it here eventually?