Workaround for PathMeasure.getSegment() behavior change

SkPathMeasure::getSegment(SkScalar startD, SkScalar stopD, SkPath* dst,
bool startWithMoveTo) in SkPathMeasure used to ignore the case when
startD == stopD in MNC release. In NYC, the same paramaters would yield
a tiny segment, which leaves undesirable artifacts as shown in the bug
below.

Bug: 27665826
Change-Id: I8289dc32773fd55d686458183af44ff072866c6e