minor code optimizations

src/com/owncloud/android/datamodel/OCFile.java

@@ -31,7 +31,6 @@ import android.webkit.MimeTypeMap;
 import com.owncloud.android.lib.common.utils.Log_OC;
 
 import java.io.File;
-import java.util.Enumeration;
 
 import third_parties.daveKoeller.AlphanumComparator;
 public class OCFile implements Parcelable, Comparable<OCFile> {

src/com/owncloud/android/files/FileMenuFilter.java

@@ -226,6 +226,7 @@ public class FileMenuFilter {
         } else {
             toShow.add(R.id.action_unfavorite_file);
         }
+
     }
 
 }

src/com/owncloud/android/ui/activity/FileDisplayActivity.java

@@ -706,6 +706,7 @@ public class FileDisplayActivity extends HookActivity
             Toast t = Toast.makeText(this, getString(R.string.filedisplay_no_file_selected),
                     Toast.LENGTH_LONG);
             t.show();
+            return;
         }
     }
 

src/com/owncloud/android/ui/fragment/OCFileListFragment.java

@@ -27,7 +27,6 @@ import android.content.Context;
 import android.content.Intent;
 import android.content.SharedPreferences;
 import android.os.Bundle;
-import android.support.v4.content.ContextCompat;
 import android.support.v4.widget.SwipeRefreshLayout;
 import android.view.ContextMenu;
 import android.view.Menu;
@@ -58,7 +57,6 @@ import com.owncloud.android.ui.dialog.RenameFileDialogFragment;
 import com.owncloud.android.ui.preview.PreviewImageFragment;
 import com.owncloud.android.ui.preview.PreviewMediaFragment;
 import com.owncloud.android.ui.preview.PreviewTextFragment;
-import com.owncloud.android.utils.DisplayUtils;
 import com.owncloud.android.utils.FileStorageUtils;
 
 import java.io.File;

src/com/owncloud/android/utils/DisplayUtils.java

@@ -22,21 +22,9 @@
 
 package com.owncloud.android.utils;
 
-import java.io.File;
-import java.net.IDN;
-import java.text.DateFormat;
-import java.util.Arrays;
-import java.util.Calendar;
-import java.util.Date;
-import java.util.HashMap;
-import java.util.HashSet;
-import java.util.Set;
-import java.util.Vector;
-
 import android.annotation.TargetApi;
 import android.app.Activity;
 import android.content.Context;
-import android.content.SharedPreferences;
 import android.graphics.Point;
 import android.graphics.PorterDuff;
 import android.os.Build;
@@ -47,7 +35,6 @@ import android.widget.SeekBar;
 
 import com.owncloud.android.MainApp;
 import com.owncloud.android.R;
-import com.owncloud.android.datamodel.FileDataStorageManager;
 import com.owncloud.android.datamodel.OCFile;
 
 import java.math.BigDecimal;