Final Text & Selection Inset Fix

[thecoolwinter]

Description

The linked pull request revealed issues with how we draw selections. This finishes a series of patches finishing exactly how we can inset text and selections. This change makes multi-line selections select only text regions, rather than being determined by the available space to draw selections, making multi-line selections draw uniformly.

It also simplifies the drawing logic, using a single function for determining all selection drawing rects, rather than three different logic paths.

The issue mentioned in the linked pr has been opened on this repository. I'll be opening a related pr in CESE reverting that change for a later update.

Related Issues

• Adjust Gutter Background, Add Trailing Padding CodeEditSourceEditor#272
• ✨ Trailing Padding When Not Wrapping #66

Checklist

• I read and understood the contributing guide as well as the code of conduct
• The issues this PR addresses are related to each other
• My changes generate no new warnings
• My code builds and runs on my machine
• My changes are all related to the related issue above
• I documented my code

Screenshots

Note the trailing padding, and the leading single selection spacing. After this change, we can inset the leading textInset and still have correct multi-line selections.

After this change (in CESE):

Before: