Make the default calorie to invalid. Fix an error while calculating the cycling calorie.

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

@@ -134,15 +134,15 @@ public class CalorieUtils {
    * @param grade the grade to calculate
    * @param weight of rider plus bike, in kilogram
    * @param timeUsed how many times used in second
-   * @return the power value watts(Joule/second).
+   * @return the calorie value in kcal.
    */
   @VisibleForTesting
   static double calculateCyclingCalorie(double speed, double grade, int weight, double timeUsed) {
     // Get the Power, the unit is Watt (Joule/second)
     double power = earthGravity * weight * speed * (K1 + grade) + K2 * (speed * speed * speed);
 
-    // Get the calories
+    // Get the calories in kcal
-    return power * timeUsed / UnitConversions.KCAL_TO_J;
+    return power * timeUsed / UnitConversions.KCAL_TO_J / 1000 ;
   }
 
   /**

MyTracksLib/src/com/google/android/apps/mytracks/stats/TripStatistics.java

@@ -62,16 +62,15 @@ public class TripStatistics implements Parcelable {
   // The min and max grade seen on this trip.
   private final ExtremityMonitor gradeExtremities = new ExtremityMonitor();
 
-  // The calorie of current track.
-  private double calorie;
-
-  
   /**
    * This value means the calorie value is invalid due to activity type is not
    * supported.
    */
   public static final double INVALID_CALORIE = -1.0;
 
+  // The calorie of current track.
+  private double calorie = INVALID_CALORIE;
+
   /**
    * Default constructor.
    */