Merge "camera3: Update whiteLevel/greenSplit docs."

     * each channel is specified by the offset in the

     * {@link CameraCharacteristics#SENSOR_BLACK_LEVEL_PATTERN android.sensor.blackLevelPattern} tag.</p>

     * <p>The white level is typically determined either by sensor bit depth

     * (10-14 bits is expected), or by the point where the sensor response

     * (8-14 bits is expected), or by the point where the sensor response

     * becomes too non-linear to be useful.  The default value for this is

     * maximum representable value for a 16-bit raw sample (2^16 - 1).</p>

     *

     * filter array.</p>

     * <p>The green split is calculated as follows:</p>

     * <ol>

     * <li>A representative 5x5 pixel window W within the active

     * sensor array is chosen.</li>

     * <li>A 5x5 pixel (or larger) window W within the active sensor array is

     * chosen. The term 'pixel' here is taken to mean a group of 4 Bayer

     * mosaic channels (R, Gr, Gb, B).  The location and size of the window

     * chosen is implementation defined, and should be chosen to provide a

     * green split estimate that is both representative of the entire image

     * for this camera sensor, and can be calculated quickly.</li>

     * <li>The arithmetic mean of the green channels from the red

     * rows (mean_Gr) within W is computed.</li>

     * <li>The arithmetic mean of the green channels from the blue