Fix selection expansion across full-width glyphs

Instead of trying to expand the start and end of a selection across
full-width glyphs, the selection should now only go from its origin to
the end without any kind of expansion.

Instead, the expansion is now done where the cells are actually checked
for their selection status, expanding across the entire full-width glyph
whenever any part of it is selected.

Fixes #3106.

0 files changed, 0 insertions, 0 deletions