78d983ee led to some rounded corners in the UI not being perfectly
circular anymore: Popup messages would stretch the rounding depending on
message length, and the rounded corner of the message in the annotation
bar would get distorted while changing the sidebar's width.
That commit tried to fix the following `warning: ‘void
QPainter::drawRoundRect(int, int, int, int, int, int)’ is deprecated:
Use drawRoundedRect(..., Qt::RelativeSize)` by changing to
`drawRoundedRect`, but missed to also add `Qt::RelativeSize`.
Adding the missing flag fixes both issues. The change is also
implemented in `dviRenderer::epsf_special` (introduced in be544056,
changed in 55dc43bf) for correctness.
Test Plan:
- Start Okular. The "Welcome" message and the "Document Loaded"
message have perfectly rounded corners again, not depending
on message length.
- Change width of the annotations sidebar: The "No Annotations"
message does not change its rounded corners anymore.
- Running in HiDPI mode retains the correct behavior.
- Note: There does not seem to be a trivial/convenient way to trigger
the DVI code path.
667e73325a