Make selection end handle stick to selection at line end.

At line break, one offset can be mapped to two phisical
position: previous line end and next line start.
Previously, all cursor handles are placed at next line
start.
With this CL, selection end handle is placed at the
previous line end in such cases.

Test: FrameworksCoreTests
Bug: 21305922

Change-Id: I00d9f9a0cd417ca92534e93b3d3f655cd62f25d3