[apps/calculation] Reset history cell memoization when reloading the

table. Otherwise, the Poincare pool store useless layouts for cells that
aren't displayed.

This fixes the following issue: input "(transpose([1 2 3 4 5 6][1 2 3 4 5
6])^8", the computation works, clear the history, input the same
calculation again, it fails with a memory error.

apps/calculation/history_controller.cpp

@@ -24,6 +24,13 @@ HistoryController::HistoryController(EditExpressionController * editExpressionCo
 }
 
 void HistoryController::reload() {
+  /* When reloading, we might not used anymore cell that hold previous layouts.
+   * We clean them all before reloading their content to avoid taking extra
+   * useless space in the Poincare pool. */
+  for (int i = 0; i < k_maxNumberOfDisplayedRows; i++) {
+    m_calculationHistory[i].resetMemoization();
+  }
+
   m_selectableTableView.reloadData();
   /* TODO
    * Replace the following by selectCellAtLocation in order to avoid laying out