Revert "Make the space part of the replacement image span."

This reverts commit a1d52e92
Also reverts later change:
https://android-git.corp.google.com/g/#/c/138160/3
That was made to remove code that took into account having a space not
covered by the span character.
Fixes tests cases to respect the space character again.
Change-Id: I96d52a5df4d01e757f72949cbcf3b1f582679a46