Merge "Fix Drawable.getOpacity() docs"

     * returned.  You can use the method {@link #resolveOpacity} to perform a

     * standard reduction of two opacities to the appropriate single output.

     *

     * <p>Note that the returned value does <em>not</em> take into account a

     * <p>Note that the returned value does not necessarily take into account a

     * custom alpha or color filter that has been applied by the client through

     * the {@link #setAlpha} or {@link #setColorFilter} methods.

     * the {@link #setAlpha} or {@link #setColorFilter} methods. Some subclasses,

     * such as {@link BitmapDrawable}, {@link ColorDrawable}, and {@link GradientDrawable},

     * do account for the value of {@link #setAlpha}, but the general behavior is dependent

     * upon the implementation of the subclass.

     *

     * @return int The opacity class of the Drawable.

     *