The descriptor object of report modules in v2 plugins not initialized (null)

Steps to reproduce:

1. Download JIRA Charting Plugin 1.5-beta2.
2. Install it into JIRA (4.0-Beta3rc1)
3. Try to generate the "Workload Pie" report.

After the last step, you will get a NullPointerException. That's because the 'descriptor' object is null when the module tries to get the 'view' HTML from it.

If you remove all v2 plugin modules from the plugin descriptor (also marking it a v1 plugin) and install the plugin to WEB-INF/lib, the report will work.