Confirm repair

app/src/main/java/eu/faircode/email/FragmentOptionsMisc.java

@@ -632,6 +632,11 @@ public class FragmentOptionsMisc extends FragmentBase implements SharedPreferenc
         btnRepair.setOnClickListener(new View.OnClickListener() {
             @Override
             public void onClick(View v) {
+                new AlertDialog.Builder(view.getContext())
+                        .setTitle(R.string.title_advanced_repair)
+                        .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
+                            @Override
+                            public void onClick(DialogInterface dialog, int which) {
                                 new SimpleTask<Void>() {
                                     @Override
                                     protected void onPostExecute(Bundle args) {
@@ -684,6 +689,16 @@ public class FragmentOptionsMisc extends FragmentBase implements SharedPreferenc
                                     }
                                 }.execute(FragmentOptionsMisc.this, new Bundle(), "repair");
                             }
+                        })
+                        .setNegativeButton(android.R.string.cancel, new DialogInterface.OnClickListener() {
+                            @Override
+                            public void onClick(DialogInterface dialog, int which) {
+                                // Do nothing
+                            }
+                        })
+                        .show();
+            }
+
         });
 
         swAutostart.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {