Fudge clipRect in TextView for extra cursor width

There are a number of cases (most commonly cursor at start of line in
RTL direction) where the cursor extends past the right edge of the
clipRect. This patch adds approximately 1dp on the right side of the
clip, so that the cursor doesn't get clipped.

Bug: 18035274
Change-Id: I489825a91750742c28e445f54f9d27000accbcfb