To properly apply ellipsis, we virtually concatenate the last line and
overflowed lines after line breaking for a paragraph.
Previously, width of the concatenated line was computed by summing up all
line's width. However, the width is wrong when there are any trailing
white spaces that can be normal white spaces by concatenating lines.
With this CL, we sum up widths of all characters in lines except the last
overflowed line.
Bug: 28599066
Change-Id: I41d828ee8eb8a702cd5096d626b307cbb3467047
78f0d83550