MDL-54666 tests: Verify that any activity keeps the settings

This was affecting both to rateable (forum...) and not rateable
(assignment...) activities. So tests have been completed to verify
that now saving is performed and the correct scale values stored.

lib/form/tests/behat/modgrade_validation.feature

@@ -65,7 +65,60 @@ Feature: Using the activity grade form element
     And I should not see "You must choose whether to rescale existing grades or not"
 
   @javascript
-  Scenario: Attempting to change the scale when grades already exist
+  Scenario: Attempting to change the scale when grades already exist in rating activity
+    Given I log in as "admin"
+    And I navigate to "Scales" node in "Site administration > Grades"
+    And I press "Add a new scale"
+    And I set the following fields to these values:
+      | Name  | ABCDEF |
+      | Scale | F,E,D,C,B,A |
+    And I press "Save changes"
+    And I press "Add a new scale"
+    And I set the following fields to these values:
+      | Name  | Letter scale |
+      | Scale | Disappointing, Good, Very good, Excellent |
+    And I press "Save changes"
+    And I log out
+    And I log in as "teacher1"
+    And I follow "Course 1"
+    And I turn editing mode on
+    And I add a "Forum" to section "1" and I fill the form with:
+      | Forum name | Test forum name |
+      | Forum type | Standard forum for general use |
+      | Description | Test forum description |
+      | Aggregate type | Average of ratings  |
+      | scale[modgrade_type] | Scale |
+      | scale[modgrade_scale] | ABCDEF |
+      | Group mode | No groups |
+    And I log out
+    And I log in as "student1"
+    And I follow "Course 1"
+    And I follow "Test forum name"
+    And I press "Add a new discussion topic"
+    And I set the following fields to these values:
+      | Subject  | Discussion subject |
+      | Message | Discussion message |
+    And I press "Post to forum"
+    And I log out
+    And I log in as "teacher1"
+    And I follow "Course 1"
+    And I follow "Test forum name"
+    And I follow "Discussion subject"
+    And I set the field "rating" to "D"
+    And I click on "Edit settings" "link" in the "Administration" "block"
+    When I expand all fieldsets
+    Then I should see "Some grades have already been awarded, so the grade type and scale cannot be changed"
+    # Try saving the form and visiting it back to verify that everything is working ok.
+    And I press "Save and display"
+    And I should not see "When selecting a ratings aggregate type you must also select"
+    And I click on "Edit settings" "link"
+    And I expand all fieldsets
+    And the field "Aggregate type" matches value "Average of ratings"
+    And the field "scale[modgrade_type]" matches value "Scale"
+    And the field "scale[modgrade_scale]" matches value "ABCDEF"
+
+  @javascript
+  Scenario: Attempting to change the scale when grades already exist in non-rating activity
     Given I log in as "admin"
     And I navigate to "Scales" node in "Site administration > Grades"
     And I press "Add a new scale"
@@ -97,6 +150,12 @@ Feature: Using the activity grade form element
     And I click on "Edit settings" "link"
     When I expand all fieldsets
     Then I should see "Some grades have already been awarded, so the grade type and scale cannot be changed"
+    # Try saving the form and visiting it back to verify everything is working ok.
+    And I press "Save and display"
+    And I click on "Edit settings" "link"
+    And I expand all fieldsets
+    And the field "grade[modgrade_type]" matches value "Scale"
+    And the field "grade[modgrade_scale]" matches value "ABCDEF"
 
   Scenario: Attempting to change the maximum grade when ratings exist
     Given I log in as "teacher1"