Spell checking in TextViews

New UX interactions (the Paste action is no longer displayed after a delay)
suggestionEnabled flag replaced by existing input type flag.
removeSpans fixed in SpannableStringBuilder to always send notifications
SuggestionSpan handled by TextView instead of SpannableStringBuilder

New span update algorithm to correctly handle edition around word boundaries.

Change-Id: I52c01172f19e595fa512e285a565a3fd97c3c50e
15 files changed