Test SCH_SHEET rotation and mirroring

qa/eeschema/test_sch_item.cpp

@@ -78,13 +78,22 @@ static SCH_ITEM* Instatiate( KICAD_T aType, SCH_SHEET* sheet )
     case SCH_SYMBOL_T: return new SCH_SYMBOL();
 
     case SCH_SHEET_PIN_T:
-        // XXX: Sheet pins need to be manually placed on sheet item side.
+        // XXX (?): Sheet pins currently have to have their initial positions calculated manually.
         return new SCH_SHEET_PIN(
                 sheet,
                 wxPoint( sheet->GetPosition().x, sheet->GetPosition().y + Millimeter2iu( 40 ) ),
                 "test pin" );
 
     case SCH_SHEET_T:
+    {
+        SCH_SHEET* sheet = new SCH_SHEET();
+        sheet->SetSize( wxSize( Millimeter2iu( 100 ), Millimeter2iu( 50 ) ) );
+
+        // XXX (?): Sheet fields currently have to be positioned with an additional method call.
+        sheet->AutoplaceFields( nullptr, false );
+        return sheet;
+    }
+
     case SCH_PIN_T:
     case SCHEMATIC_T:
         // TODO