SearchView does not open if Toolbar elevation is set

[IgorKrupenja]

Steps:

1. Open the sample app project in Android Studio.
2. Add the android:elevation="2dp" attribute to android.support.v7.widget.Toolbar in `activity_main.xml.
3. Run app.
4. Click on search icon (magnifying glass).

Expected result:
SearchView opens correctly and you can input text.

Actual result:
SearchView does not open, animation does not play. Keyboard actually appears on screen but pressing keys has no result.

Sample app works OK without the android:elevation="2dp" attribute. Note that I never had any problems using elevation in own projects.