When a line had only whitespace changes that the user had configured to
be ignored, the previous behavior was to not show those at all, and if
the line showed up as context, render the right-side version of that
line both left and right. That is very confusing.
The new behavior is to not use colors to highlight those changes, but
still render the left and right as the files actually are.
Bug: Issue 1062
Change-Id: Ic301cc5445d33ee6e0a780178a189386669f8a7a
80df1f3f0f