Cleanup using AndroidStudio code analyzer.

Moved to iterator for loops for ChartView and ChartFragment.

src/main/java/de/dennisguse/opentracks/services/LocationListenerPolicy.java

@@ -21,7 +21,7 @@ package de.dennisguse.opentracks.services;
  *
  * @author Sandor Dornbush
  */
-public interface LocationListenerPolicy {
+interface LocationListenerPolicy {
 
     /**
      * Returns the polling interval this policy would like at this moment.

src/main/java/de/dennisguse/opentracks/services/TrackRecordingServiceConnection.java

@@ -70,7 +70,7 @@ public class TrackRecordingServiceConnection implements ServiceConnection, Death
     /**
      * Binds the service if it is started.
      */
-    public void bindIfStarted(Context context) {
+    private void bindIfStarted(Context context) {
         bindService(context, false);
     }
 

src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskExecutor.java

@@ -30,7 +30,6 @@ import de.dennisguse.opentracks.util.UnitConversions;
 public class PeriodicTaskExecutor {
 
     private static final String TAG = PeriodicTaskExecutor.class.getSimpleName();
-    private static final long MINUTE_TO_MILLISECONDS = 60000L;
 
     private final TrackRecordingService trackRecordingService;
     private final PeriodicTaskFactory periodicTaskFactory;
@@ -93,7 +92,7 @@ public class PeriodicTaskExecutor {
             if (timerTaskExecutor == null) {
                 timerTaskExecutor = new TimerTaskExecutor(periodicTask, trackRecordingService);
             }
-            timerTaskExecutor.scheduleTask(taskFrequency * MINUTE_TO_MILLISECONDS);
+            timerTaskExecutor.scheduleTask(taskFrequency * UnitConversions.ONE_MINUTE_MS);
         } else {
             // For distance periodic task
             calculateNextTaskDistance();

src/main/java/de/dennisguse/opentracks/services/tasks/PeriodicTaskFactory.java

@@ -23,7 +23,7 @@ import android.content.Context;
  *
  * @author Sandor Dornbush
  */
-public interface PeriodicTaskFactory {
+interface PeriodicTaskFactory {
 
     /**
      * Creates a {@link PeriodicTask}.