codacy: fix newly created issues

src/main/java/com/owncloud/android/ui/activity/PassCodeActivity.java

@@ -331,7 +331,7 @@ public class    PassCodeActivity extends AppCompatActivity {
 
         boolean result = true;
         for (int i = 0; i < mPassCodeEditTexts.length && result; i++) {
-            result = (mPassCodeEditTexts[i].getText().toString()).equals(mPassCodeDigits[i]);
+            result = mPassCodeEditTexts[i].getText().toString().equals(mPassCodeDigits[i]);
         }
         return result;
     }

src/main/java/com/owncloud/android/ui/activity/ReceiveExternalFilesActivity.java

@@ -131,6 +131,7 @@ public class ReceiveExternalFilesActivity extends FileActivity
     public static final String URL_FILE_SUFFIX = ".url";
     public static final String WEBLOC_FILE_SUFFIX = ".webloc";
     public static final String DESKTOP_FILE_SUFFIX = ".desktop";
+    public static final int SINGLE_PARENT = 1;
 
     private AccountManager mAccountManager;
     private Stack<String> mParents = new Stack<>();
@@ -1063,7 +1064,7 @@ public class ReceiveExternalFilesActivity extends FileActivity
                 dialog.show(getSupportFragmentManager(), CreateFolderDialogFragment.CREATE_FOLDER_FRAGMENT);
                 break;
             case android.R.id.home:
-                if (mParents.size() > 1) {
+                if (mParents.size() > SINGLE_PARENT) {
                     onBackPressed();
                 }
                 break;

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

@@ -27,7 +27,6 @@ package com.owncloud.android.utils;
 import android.accounts.Account;
 import android.accounts.AccountManager;
 import android.annotation.SuppressLint;
-import android.annotation.TargetApi;
 import android.app.Activity;
 import android.content.Context;
 import android.content.Intent;