JobsListTests GWT unit test very slow

[gtritchie]

#6352 # System details

RStudio Edition : Server (dev)
RStudio Version : master after merging #6592
OS Version      : any
R Version       : any

Steps to reproduce the problem

Build and run ant unittest

Describe the problem in detail

Tests take upwards of 2 minutes to run.

Describe the behavior you expected

Prior to merging PR #6592 (custom fonts for RStudio Server) these were taking ~< 20 seconds to run.

The problem is that the JobsListTests suite is creating UI, which in turn causes calls to static WebThemeFontLoader.getFixedWidthFont(), which makes direct injector calls to get SessionInfo and UserPrefs. We shouldn't be doing this in unit tests. Ideally we'd refactor to avoid creating UI in our unit tests, and/or not be making direct injector calls like this but instead using mocked versions.

See #4460 for a previous set of fixes for this type of issue.