bool LayerTextureUpdaterSkPicture::createFrameBuffer()
{
    ASSERT(!m_fbo);
    ASSERT(!m_bufferSize.isEmpty());

    // SKIA only needs color and stencil buffers, not depth buffer.
    // But it is very uncommon for cards to support color + stencil FBO config.
    // The most common config is color + packed-depth-stencil.
    // Instead of iterating through all possible FBO configs, we only try the
    // most common one here.
    // FIXME: Delegate the task of creating frame-buffer to SKIA.
    // It has all necessary code to iterate through all possible configs
    // and choose the one most suitable for its purposes.
    Extensions3D* extensions = context()->getExtensions();
    if (!extensions->supports("GL_OES_packed_depth_stencil"))
        return false;
    extensions->ensureEnabled("GL_OES_packed_depth_stencil");

    // Create and bind a frame-buffer-object.
    m_fbo = context()->createFramebuffer();
    if (!m_fbo)
        return false;
    context()->bindFramebuffer(GraphicsContext3D::FRAMEBUFFER, m_fbo);

    // We just need to create a stencil buffer for FBO.
    // The color buffer (texture) will be provided by tiles.
    // SKIA does not need depth buffer.
    m_depthStencilBuffer = context()->createRenderbuffer();
    if (!m_depthStencilBuffer) {
        deleteFrameBuffer();
        return false;
    }
    context()->bindRenderbuffer(GraphicsContext3D::RENDERBUFFER, m_depthStencilBuffer);
    context()->renderbufferStorage(GraphicsContext3D::RENDERBUFFER, Extensions3D::DEPTH24_STENCIL8, m_bufferSize.width(), m_bufferSize.height());
    context()->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::DEPTH_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, m_depthStencilBuffer);
    context()->framebufferRenderbuffer(GraphicsContext3D::FRAMEBUFFER, GraphicsContext3D::STENCIL_ATTACHMENT, GraphicsContext3D::RENDERBUFFER, m_depthStencilBuffer);

    // Create a skia gpu canvas.
    GrContext* skiaContext = m_context->grContext();
    GrPlatformSurfaceDesc targetDesc;
    targetDesc.reset();
    targetDesc.fSurfaceType = kRenderTarget_GrPlatformSurfaceType;
    targetDesc.fRenderTargetFlags = kNone_GrPlatformRenderTargetFlagBit;
    targetDesc.fWidth = m_bufferSize.width();
    targetDesc.fHeight = m_bufferSize.height();
    targetDesc.fConfig = kRGBA_8888_GrPixelConfig;
    targetDesc.fStencilBits = 8;
    targetDesc.fPlatformRenderTarget = m_fbo;
    SkAutoTUnref<GrRenderTarget> target(static_cast<GrRenderTarget*>(skiaContext->createPlatformSurface(targetDesc)));
    SkAutoTUnref<SkDevice> device(new SkGpuDevice(skiaContext, target.get()));
    m_canvas = adoptPtr(new SkCanvas(device.get()));

    context()->bindFramebuffer(GraphicsContext3D::FRAMEBUFFER, 0);
    return true;
}