AI 143728: Fix # 1743137: Suggestion bubble doesn't go away after empty space...

AI 143728: Fix # 1743137: Suggestion bubble doesn't go away after empty space on right end of suggestion strip is tapped.
  The empty space on right end sometimes registers as the word at the left end. Fixed this by checking for -1.
  Also fixed a bug where the strip moves in the wrong direction on drag, when it shouldn't move at all.
  BUG=1743137

Automated import of CL 143728