goLineLeft behaving incorrectly for wrapped lines

When goLineLeft executed when cursor at the end of the visual line, it tends to go to the beginning of next one.

steps to repro:

1. go to http://codemirror.net/demo/indentwrap.html (again, demonstrating on indentwrap due to lack of pure lineWrapping demo, but applies to both)

2. paste this into console and click back inside the editor within the 2s period

   setTimeout(() => { editor.setCursor({line: 4, ch: 71}); editor.execCommand("goLineLeft"); }, 2000 );
   

Similarly (but much less aggravating… in fact I think it’s a nice behavior), if goLineRight is executed at the end of a visual line, it goes to the end of the next visual line.

[marijnh]

The output of charCoords for wrapped characters is pretty much undefined, since browsers do wildly different weird things for those. This is why we have cursorCoords, which gives you the coordinates of an actual cursor position, which is easier to define.

Attached patch makes goLineRight stable (i.e. it stops advancing when the cursor is already at the end of the line). Does that solve the problem for you?

[dwelle]

WTBS, goLineLeftSmart should use the same.