Fix maxscale

[yangshiliang]

First, revert back to old logic for layout change listener. old logic
It should fix #452 and #493.
Because when we are trying to set an initial scale by setScale, even if we are posting a runnable, onLayoutChange will be triggered after setScale. Inside onLayoutChange, updateBaseMatrix will reset the mSuppMatrix. Then setScale won't work for the initial setScale.

Second, add public methods getSuppMatrix and setSuppMatrix to save and restore scale and visible area, which should fix #509.

Third, sometimes the user can zoom the image larger than the max scale, which happens when we move the two fingers close first and then far away with a fling. We should make the image zoom back to the max scale.

Last, if we force the image to zoom back to max scale, with the above gesture, sometimes it causes the boundary issue. Please see the gif. So we should do checkMatrixBounds for the fling.

[yangshiliang]

I used the following code to save and restore the state.

/// To save:
Matrix matrix = new Matrix();
float[] matrixValues = new float[9];
mPhotoView.getSuppMatrix(matrix);
matrix.getValues(matrixValues);
outState.putFloatArray(mKeySuppMatrixValues, matrixValues);

/// To restore:
float[] values = savedInstanceState.getFloatArray(mKeySuppMatrixValues);
mInitialSuppMatrix = new Matrix();
mInitialSuppMatrix.setValues(values);

mPhotoView.post(new Runnable() {
    @Override
    public void run() {
        mPhotoView.setSuppMatrix(mInitialSuppMatrix);
    }
});

[Jawnnypoo]

Can you rebase this?

[yangshiliang]

Done. Please review.

[Jawnnypoo]

Thanks