Regression: Performance of BorderImage has significantly decreased

import QtQuick 2.0

Item {
    width: 800; height: 800
    Grid {
        anchors.fill: parent
        columns: 8

        Repeater {
            id: buttonRepeater
            BorderImage {
                width: 100
                height: 50

                border {
                    left: 15
                    right: 15
                    top: 15
                    bottom: 15
                }

                source: "button-border.png"
            }
        }
    }

    MouseArea {
        anchors.fill: parent
        onClicked: buttonRepeater.model = 128
    }
}

   - compiling material: 0ms
   - AtlasTexture(30x31), uploaded in 0 ms
 - Gui Thread: window=0x88d0240, polish=0, lock=0, block/sync=7 -- animations=0
 - Breakdown of render time: preprocess=0, updates=0, binding=0, render=13, total=13
Render Thread: window=0x88d0240, framedelta=1837, sync=0, first render=13, after final swap=0

qt.scenegraph.time.renderloop: Frame prepared with 'threaded' renderloop, polish=0, lock=0, blockedForSync=65, animations=0 - (on Gui thread) QQuickView(0x933b648)
qt.scenegraph.time.compilation: shader compiled in 0ms
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (15x15)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (1x15)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (15x15)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (15x1)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (1x1)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (15x1)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (15x15)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (1x15)
qt.scenegraph.time.texture: atlastexture uploaded in: 0ms (15x15)
...above 9 uploads repeated 128 times....

qt.scenegraph.time.compilation: shader compiled in 0ms
qt.scenegraph.time.renderer: time in renderer: total=67ms, preprocess=0, updates=0, binding=0, rendering=66
qt.scenegraph.time.renderloop: Frame rendered with 'threaded' renderloop in 132ms, sync=65, render=67, swap=0 - (on render thread)