Previously a Painter's m_clip_origin field was initialized to a
widget's window_relative_rect, which is not ensured to be within
the target rect.
m_clip_origin is normally not used for clipping, but after calling
clear_clip_rect the clip rect that IS used for clipping gets reset
to m_clip_origin (so an invalid state is entered).
Now the window_relative_rect will be clipped by the target rect
first, and will only then be used to initialize both the active
clip_rect and m_clip_origin.
SPDX License Identifiers are a more compact / standardized
way of representing file license information.
See: https://spdx.dev/resources/use/#identifiers
This was done with the `ambr` search and replace tool.
ambr --no-parent-ignore --key-from-file --rep-from-file key.txt rep.txt *