WebGLLayerWebKitThread::WebGLLayerWebKitThread()
    : LayerWebKitThread(WebGLLayer, 0)
    , m_webGLContext(0)
    , m_needsDisplay(false)
{
    setLayerProgramShader(LayerProgramShaderRGBA);
}
void CanvasLayerWebKitThread::setDevice(SkGpuDevice* device)
{
    m_device = device;
    setLayerProgramShader(LayerProgramShaderRGBA);
    setNeedsDisplay();
}