Fix: Wrong suggestion popup position in extract mode.

Replace text was handled by the original EditText; thus, we
couldn't correctly decide popup window position.
Also, changing selection range replaces entire text of the
extracted EditText. As a result, text cannot be replaced
with the selected item when there is a selection.

This change is a workaround for this issue. This quits
offering "Replace" for selection in extract mode.

Bug: 22038802
Change-Id: I052b027cfd10eeb289f77f4c6b228acf58fea636