Extend MediaScanner and MtpDatabase to support RAW image files

Bug: 25871812
Change-Id: Iee92632585dc9020238a9b562defd06d6d2a91dc
diff --git a/media/java/android/mtp/MtpDatabase.java b/media/java/android/mtp/MtpDatabase.java
index bc96e2e..29bcc19 100755
--- a/media/java/android/mtp/MtpDatabase.java
+++ b/media/java/android/mtp/MtpDatabase.java
@@ -587,6 +587,7 @@
             MtpConstants.FORMAT_PLS_PLAYLIST,
             MtpConstants.FORMAT_XML_DOCUMENT,
             MtpConstants.FORMAT_FLAC,
+            MtpConstants.FORMAT_DNG,
         };
     }
 
@@ -696,6 +697,7 @@
             case MtpConstants.FORMAT_GIF:
             case MtpConstants.FORMAT_PNG:
             case MtpConstants.FORMAT_BMP:
+            case MtpConstants.FORMAT_DNG:
                 return IMAGE_PROPERTIES;
             default:
                 return FILE_PROPERTIES;