Artifacts when resizing EGit blame window at 150% monitor zoom

[HeikoKlare]

Description
On specific monitor zooms (such as 150%), the popup window for blame information on specific lines in EGit shows rendering artifacts when resizing it.

This might be related to:

• Artifacts when resizing column of TableViewer with StyledCellLabelProvider #548

Reproduction

• Open a current IDE on a 150% monitor
• Open any Java file under Git version control and show the revision information in the ruler (right click -> "Team" -> "Show revision information")
• Hover over any of the markers with changes, such that the window with detail information appears
• Slowing increase the width of that window

Expected Behavior
On resizing, the information should be properly rendering (clearly readable without any artifacts).