camera3: Update whiteLevel/greenSplit docs.

Bug: 13191430
Change-Id: I61cab65da546bdf1a748f46c28b6fce218b27bc4
diff --git a/core/java/android/hardware/camera2/CameraCharacteristics.java b/core/java/android/hardware/camera2/CameraCharacteristics.java
index 45d6e88..37bead8 100644
--- a/core/java/android/hardware/camera2/CameraCharacteristics.java
+++ b/core/java/android/hardware/camera2/CameraCharacteristics.java
@@ -1007,7 +1007,7 @@
      * 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>
      *
diff --git a/core/java/android/hardware/camera2/CaptureResult.java b/core/java/android/hardware/camera2/CaptureResult.java
index 7eb63d6..f528bdd 100644
--- a/core/java/android/hardware/camera2/CaptureResult.java
+++ b/core/java/android/hardware/camera2/CaptureResult.java
@@ -1720,8 +1720,12 @@
      * 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