safe fix reaviz#223

src/layout/utils.ts

@@ -12,7 +12,10 @@ export function measureText(text: string) {
   let result = { height: 0, width: 0 };
 
   if (text) {
-    result = calculateSize(text, {
+    // @ts-ignore
+    // Reference: https://github.com/reaviz/reaflow/pull/229
+    const fn = calculateSize || calculateSize.default;
+    result = fn(text, {
       font: 'Arial, sans-serif',
       fontSize: '14px'
     });