Unhide inPreferQualityOverSpeed in BitmapFactory.Options.

The new field allows a developer to use a more accurate by
slightly slower IDCT method in JPEG decode. This in turns improves the
quality of the reconstructed image.

The field by default is not set and thus does not affect existing
applications.

Bug: 3238925

Related changes: https://android-git.corp.google.com/g/#change,83291 and
                 https://android-git.corp.google.com/g/#change,83294

Change-Id: I969f5c413f9b2179454aeb90e18ae8222ee583b4

graphics/java/android/graphics/BitmapFactory.java

@@ -210,7 +210,6 @@ public class BitmapFactory {
          * expense of the decoding speed. Currently the field only affects JPEG
          * decode, in the case of which a more accurate, but slightly slower,
          * IDCT method will be used instead.
-         * @hide
          */
         public boolean inPreferQualityOverSpeed;