Add tests for rename documents feature

    - Add helper class for the Ui tests. It creates basic test environment.
      It is intermediate layer between UiBot/DocumentsProviderHelper and UiTest classes.
    - Refactor SearchView tests
    - Add renaming support in the test DocumentsProvider
    - Add renaming tests

Bug=26799799

Change-Id: I2849913a1addabff0087bb06b80f36de7cb144f3