What options does MAT have for continuing to use BIRT charting?
One option is MAT to contribute the BIRT bundles it uses.
I have provided a bug with associated gerrits that do this: See Bug 568134
and associated gerrits.
for that issue and provided a gerrit.
If both those bugs are accepted, then BIRT can be removed (see change 171143
- I validated this change with a locally rebuilt MAT)