resetBackBuffer never hides the backbuffer tile

[ksgeograf]

In Tile/Image.js the comments for "resetBackBuffer" are:

    /** 
     * Method: resetBackBuffer
... omitted lines ....
     *  - If layer is still loading, show foreground tile but don't hide
     *    the backBufferTile yet
     *  - If layer is done loading, reset backBuffer tile and show 
     *    foreground tile
     */

But the code never hides the backbuffer tile. Even when no more tiles are supposed to load (ea this.layer.numLoadingTiles == 0).

I have a map were the overlays are semi-transparent, and this means that the color gets applied twice, making it appear darker.

The attached patch fixes the problem by hiding the backBufferTile.

[ksgeograf]

File attached to 1926, this was a mispost.