Add private constructor to utility classes

MyTracks/src/com/google/android/apps/mytracks/util/GoogleFeedbackUtils.java

@@ -42,6 +42,8 @@ public class GoogleFeedbackUtils {
 
   private static Boolean available = null;
 
+  private GoogleFeedbackUtils() {}
+
   /**
    * Returns true if the Google Feedback is available.
    * 

MyTracks/src/com/google/android/apps/mytracks/util/GoogleLocationUtils.java

@@ -33,6 +33,8 @@ public class GoogleLocationUtils {
   private static final String
       ACTION_GOOGLE_APPS_LOCATION_SETTINGS = "com.google.android.gsf.GOOGLE_APPS_LOCATION_SETTINGS";
 
+  private GoogleLocationUtils() {}
+
   /**
    * Returns true if the Google location settings is available.
    */