Bookmarked line coloring is wrong when Selection Margin is disabled

[PaulSquires]

Bookmarked line coloring is wrong when Selection Margin is disabled. For example, when margin is enabled, the margin icon will display for each bookmarked line using a white colour, however, if the margin is disabled then the entire line will be coloured white instead.

This behaviour is consistent with the expected behaviour per the Scintilla documentation (https://scintilla.org/ScintillaDoc.html under the Markers section):

Markers appear in the selection margin to the left of the text. If the selection margin is set to zero width, the background colour of the whole line is changed instead.