Merge "Revert "Change behavior of setBitmap to cleanly reset the canvas -...

    /**

     * Specify a bitmap for the canvas to draw into. All canvas state such as

     * layers, filters, and the save/restore stack are reset. Additionally,

     * layers, filters, and the save/restore stack are reset with the exception

     * of the current matrix and clip stack. Additionally, as a side-effect

     * the canvas' target density is updated to match that of the bitmap.

     *

     * Prior to API level {@value Build.VERSION_CODES#O} the current matrix and

     * clip stack were preserved.

     *

     * @param bitmap Specifies a mutable bitmap for the canvas to draw into.

     * @see #setDensity(int)

     * @see #getDensity()

// Canvas state operations: Replace Bitmap

// ----------------------------------------------------------------------------

class ClipCopier : public SkCanvas::ClipVisitor {

public:

    explicit ClipCopier(SkCanvas* dstCanvas) : m_dstCanvas(dstCanvas) {}

    virtual void clipRect(const SkRect& rect, SkClipOp op, bool antialias) {

        m_dstCanvas->clipRect(rect, op, antialias);

    }

    virtual void clipRRect(const SkRRect& rrect, SkClipOp op, bool antialias) {

        m_dstCanvas->clipRRect(rrect, op, antialias);

    }

    virtual void clipPath(const SkPath& path, SkClipOp op, bool antialias) {

        m_dstCanvas->clipPath(path, op, antialias);

    }

private:

    SkCanvas* m_dstCanvas;

};

void SkiaCanvas::setBitmap(const SkBitmap& bitmap) {

    mCanvasOwned.reset(new SkCanvas(bitmap));

    mCanvas = mCanvasOwned.get();

    SkCanvas* newCanvas = new SkCanvas(bitmap);

    if (!bitmap.isNull()) {

        // Copy the canvas matrix & clip state.

        newCanvas->setMatrix(mCanvas->getTotalMatrix());

        ClipCopier copier(newCanvas);

        mCanvas->replayClips(&copier);

    }

    // deletes the previously owned canvas (if any)

    mCanvasOwned = std::unique_ptr<SkCanvas>(newCanvas);

    mCanvas = newCanvas;

    // clean up the old save stack

    mSaveStack.reset(nullptr);

}