Reported by Lummox JR on behalf of Chowder, per comments in issue 2891

Descriptive Problem Summary:
Selecting a 1x1 region of an icon in the pixmap editor, then right-clicking to clear the selection, will not allow that same pixel to be re-selected.

Numbered Steps to Reproduce Problem:
1) Open an icon in the pixmap editor.
2) Using the selection tool, click any pixel.
3) Right-click to clear selection.
4) Click the same pixel again.

Expected Results:
A 1x1 selection should be created, just like it was the first time.

Actual Results:
The same pixel cannot be re-selected by itself.