Use faster check for line whether it's inside drawing rect

[danielgindi]

This obviously does not consider slope that's outside,
But these cases will be clipping by CoreGraphics anyway.
Doing a full line collision test here is an overkill.

Issue Link 🔗

Fixes a performance degradation introduced here: #4100
It was a big chunk of code that was introduced to fix a subtle bug, but most of the fix was actually the code calling it - figuring out the first/last line coordinate for stepped lined.

Goals ⚽

Revert to almost-the-previous-implementation, keeping the actual fix in place.

Implementation Details 🚧

When testing simply that lastCoordinate.x > left && firstCoordinate.x < right, it's enough to ensure the line is horizontally somewhere in the content rect.
The equivalent vertical check was inverted, causing rare issues.
But the main issue was actually with stepped lines, where a line was more than 2 coordinates, and only the first 2 were validated.

Testing Details 🔍

Zooming in manually in all scenarios until all coordinates are off screen - horizontally and vertically.