MDL-45068 groups: fixes to group import

- If 'coursename' is specified in the CSV it should match the course short name - thanks Yusuf Yılmaz for the patch
- If 'idnumber' is specified but 'groupidnumber' is not, idnumber should be used for matching the course idnumber only
- If 'groupingname' is not specified, there should be no notices (regression from MDL-42514)
- If 'coursename' or 'idnumber' column is present, it can contain empty values in some/all lines

group/tests/behat/groups_import.feature

@@ -8,12 +8,14 @@ Feature: Importing of groups and groupings
     Given the following "courses" exist:
       | fullname | shortname | category |
       | Course 1 | C1 | 0 |
+      | Course 2 | C2 | 0 |
     And the following "users" exist:
       | username | firstname | lastname | email |
       | teacher1 | Teacher | 1 | teacher1@example.com |
     And the following "course enrolments" exist:
       | user | course | role |
       | teacher1 | C1 | editingteacher |
+      | teacher1 | C2 | editingteacher |
 
   @javascript
   Scenario: Import groups and groupings as teacher
@@ -110,3 +112,32 @@ Feature: Importing of groups and groupings
     And I press "Edit group settings"
     And the field "id_idnumber" matches value ""
     And I press "Cancel"
+
+  @javascript
+  Scenario: Import groups into multiple courses as a teacher
+    Given I log in as "teacher1"
+    And I am on "Course 1" course homepage
+    And I navigate to "Users > Groups" in current page administration
+    And I press "Import groups"
+    When I upload "group/tests/fixtures/groups_import_multicourse.csv" file to "Import" filemanager
+    And I press "Import groups"
+    Then I should see "Group group7 added successfully"
+    And I should see "Unknown course named \"C-non-existing\""
+    And I should see "Group group8 added successfully"
+    And I should not see "group-will-not-be-created"
+    And I should see "Group group9 added successfully"
+    And I should see "Group group10 added successfully"
+    And I press "Continue"
+    And I should see "group10"
+    And I should see "group7"
+    And I should see "group8"
+    And I should not see "group9"
+    And I should not see "group-will-not-be-created"
+    And I am on "Course 2" course homepage
+    And I navigate to "Users > Groups" in current page administration
+    And I should see "group9"
+    And I should not see "group-will-not-be-created"
+    And I should not see "group7"
+    And I should not see "group8"
+    And I should not see "group10"
+    And I log out

group/tests/fixtures/groups_import_multicourse.csv

@@ -0,0 +1,6 @@
+coursename,groupname
+C1,group7
+C-non-existing,group-will-not-be-created
+C1,group8
+C2,group9
+,group10