bugfix: Role "file-editor" does not have resharing permissions

Similar to the generich "editor" role the "file-editor" should have resharing
permissions.

When creating an "editor" file share using `ocs`. `ocs` already adds the `AddGrant`
permission. This commit just about fixing the mapping of resource permission back to
the corresponding role.

changelog/unreleased/fix-editor-role-resharing.md

@@ -0,0 +1,6 @@
+Bugfix: Fix definition of "file-editor" role
+
+The "file-editor" role was missing the AddGrant resource permission, which
+caused a broken mapping from ResourcePermissions to roles in certain cases.
+
+https://github.com/cs3org/reva/pull/4336

pkg/cbox/utils/conversions.go

@@ -150,7 +150,7 @@ func IntTosharePerm(p int, itemType string) *provider.ResourcePermissions {
 		if itemType == "folder" {
 			return conversions.NewEditorRole(false).CS3ResourcePermissions()
 		}
-		return conversions.NewFileEditorRole().CS3ResourcePermissions()
+		return conversions.NewFileEditorRole(false).CS3ResourcePermissions()
 	case 4:
 		return conversions.NewUploaderRole().CS3ResourcePermissions()
 	default:

pkg/conversions/role.go

@@ -154,7 +154,7 @@ func RoleFromName(name string, sharing bool) *Role {
 	case RoleSpaceEditor:
 		return NewSpaceEditorRole()
 	case RoleFileEditor:
-		return NewFileEditorRole()
+		return NewFileEditorRole(sharing)
 	case RoleUploader:
 		return NewUploaderRole()
 	case RoleManager:
@@ -271,10 +271,15 @@ func NewSpaceEditorRole() *Role {
 }
 
 // NewFileEditorRole creates a file-editor role
-func NewFileEditorRole() *Role {
+func NewFileEditorRole(sharing bool) *Role {
+	p := PermissionRead | PermissionWrite
+	if sharing {
+		p |= PermissionShare
+	}
 	return &Role{
 		Name: RoleEditor,
 		cS3ResourcePermissions: &provider.ResourcePermissions{
+			AddGrant:             sharing,
 			GetPath:              true,
 			GetQuota:             true,
 			InitiateFileDownload: true,