only add pathmeasure segment if the accumulated length was actually changed,
and not based on if the local length was > 0. This is necessary since 

    assert(delta > 0);  // true
    prevDistance = distance;
    distance += delta;
    assert(distance > prevDistance);    // not always true

Fixes https://bugs.webkit.org/show_bug.cgi?id=78979



git-svn-id: http://skia.googlecode.com/svn/trunk@3739 2bbb7eff-a529-9590-31e7-b0007b416f81
2 files changed