Use correct mime type for KML and KMZ.

src/main/java/de/dennisguse/opentracks/io/file/TrackFileFormat.java

@@ -20,18 +20,33 @@ public enum TrackFileFormat implements Parcelable {
         public TrackWriter newTrackWriter(Context context, boolean multiple) {
             return new KmlTrackWriter(context, multiple, false);
         }
+
+        @Override
+        public String getMimeType() {
+            return "application/vnd.google-earth.kml+xml";
+        }
     },
     KMZ {
         @Override
         public TrackWriter newTrackWriter(Context context, boolean multiple) {
             return new KmlTrackWriter(context, multiple, true);
         }
+
+        @Override
+        public String getMimeType() {
+            return "application/vnd.google-earth.kmz";
+        }
     },
     GPX {
         @Override
         public TrackWriter newTrackWriter(Context context, boolean multiple) {
             return new GpxTrackWriter(context.getString(R.string.app_name));
         }
+
+        @Override
+        public String getMimeType() {
+            return "application/gpx+xml";
+        }
     };
 
     public static final Creator<TrackFileFormat> CREATOR = new Creator<TrackFileFormat>() {
@@ -67,9 +82,7 @@ public enum TrackFileFormat implements Parcelable {
     /**
      * Returns the mime type for each format.
      */
-    public String getMimeType() {
-        return "application/" + getExtension() + "+xml";
-    }
+    public abstract String getMimeType();
 
     /**
      * Returns the file extension for each format.