Method prevPattern

cp-profiler/src/cpprofiler/analysis/histogram_scene.cpp:220–231

TODO: this should change scroll bar value as well

/// TODO: this should change scroll bar value as well
void HistogramScene::prevPattern()
{
    if (rects_.size() == 0)
        return;

    auto new_idx = selected_idx_ - 1;

    if (new_idx < 0)
        return;

    changeSelectedPattern(new_idx);
}

void HistogramScene::nextPattern()
{