new NeverTileDiscardPolicy()
        A 
    
    
    
    
    
    
    
    
    
    
    
    
TileDiscardPolicy specifying that tile images should never be discard.
    Methods
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    isReady()
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    Determines if the discard policy is ready to process images.Returns:True if the discard policy is ready to process images; otherwise, false.
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    shouldDiscardImage(image)
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    Given a tile image, decide whether to discard that image.Name Type Description imageImage | Promise An image, or a promise that will resolve to an image. Returns:A promise that will resolve to true if the tile should be discarded.
