camera2: Plumb DngCreator to native library.

Change-Id: Ic58bf6cf5086808b503460ef8e451fc0d6f1f850
diff --git a/core/java/android/hardware/camera2/CaptureResult.java b/core/java/android/hardware/camera2/CaptureResult.java
index d79f4b0..f91fcb9 100644
--- a/core/java/android/hardware/camera2/CaptureResult.java
+++ b/core/java/android/hardware/camera2/CaptureResult.java
@@ -33,6 +33,8 @@
  * capture. The result also includes additional metadata about the state of the
  * camera device during the capture.</p>
  *
+ * <p>{@link CameraCharacteristics} objects are immutable.</p>
+ *
  */
 public final class CaptureResult extends CameraMetadata {
 
@@ -58,6 +60,14 @@
         mSequenceId = sequenceId;
     }
 
+    /**
+     * Returns a copy of the underlying {@link CameraMetadataNative}.
+     * @hide
+     */
+    public CameraMetadataNative getNativeCopy() {
+        return new CameraMetadataNative(mResults);
+    }
+
     @Override
     public <T> T get(Key<T> key) {
         return mResults.get(key);