MOBILE-3947 assign: Do not require submission statement if empty

src/addons/mod/assign/components/submission/submission.ts

@@ -1124,9 +1124,15 @@ export class AddonModAssignSubmissionComponent implements OnInit, OnDestroy, Can
             return [];
         }
 
+        // Receved submission statement should not be undefined. It would mean that the WS is not returning the value.
         const submissionStatementMissing = !!this.assign.requiresubmissionstatement &&
             this.assign.submissionstatement === undefined;
 
+        // If received submission statement is empty, then it's not required.
+        if(!this.assign.submissionstatement && this.assign.submissionstatement !== undefined) {
+            this.assign.requiresubmissionstatement = 0;
+        }
+
         this.canSubmit = !this.isSubmittedForGrading && !this.submittedOffline && (lastAttempt.cansubmit ||
             (this.hasOffline && AddonModAssign.canSubmitOffline(this.assign, submissionStatus)));
 

src/addons/mod/assign/pages/edit/edit.ts

@@ -205,6 +205,12 @@ export class AddonModAssignEditPage implements OnInit, OnDestroy, CanLeave {
             this.introAttachments = submissionStatus.assignmentdata?.attachments?.intro ?? this.assign.introattachments;
 
             this.allowOffline = true; // If offline isn't allowed we shouldn't have reached this point.
+
+            // If received submission statement is empty, then it's not required.
+            if(!this.assign.submissionstatement && this.assign.submissionstatement !== undefined) {
+                this.assign.requiresubmissionstatement = 0;
+            }
+
             // Only show submission statement if we are editing our own submission.
             if (this.assign.requiresubmissionstatement && !this.assign.submissiondrafts && this.userId == currentUserId) {
                 this.submissionStatement = this.assign.submissionstatement;