title: Can't create a directory on /storage/emulated/0 on emulator
body: <p>I'm trying to create a directory on my android emulator but I can't do it, I already have the permission on manifest write_storage, and I get no erros but mkdir() return false, I verify if external storage is writtable too and it is, it works on physical devices my code:</p>
  
  <pre><code> /// Cria uma nova pasta para colocar o backup
      File direct = new File(Environment.getExternalStorageDirectory(),
              "/Financas RW Backup");
      try {
  
  
          if (!direct.exists()) {
              if(isExternalStorageWritable()&amp;&amp;isExternalStorageReadable()) {
                if(  direct.mkdir()) {
                    fachada.showMessage(ExportImportDB.this," Criado");
                }else{
                    fachada.showMessage(ExportImportDB.this," Não Criado");
                }
              }
          }
      } catch (Exception e) {
          fachada.showMessage(this, e.toString());
      }
  </code></pre>