1169- break out getRows

Moved getRows function from `state/stateRenderer.js` and `state/shapes.js` into `common/common.js`. Broke out section into small one line functions for replacing line breaks, then moved the `sanitize` function from `utils.js` to this new module as there is shared functionality

src/diagrams/common/common.js

@@ -0,0 +1,39 @@
+export const getRows = s => {
+  if (!s) return 1;
+  let str = breakToPlaceholder(s);
+  str = str.replace(/\\n/g, '#br#');
+  return str.split('#br#');
+};
+
+export const sanitizeText = (text, config) => {
+  let txt = text;
+  let htmlLabels = true;
+  if (
+    config.flowchart &&
+    (config.flowchart.htmlLabels === false || config.flowchart.htmlLabels === 'false')
+  )
+    htmlLabels = false;
+
+  if (config.securityLevel !== 'loose' && htmlLabels) {
+    // eslint-disable-line
+    txt = breakToPlaceholder(txt);
+    txt = txt.replace(/</g, '&lt;').replace(/>/g, '&gt;');
+    txt = txt.replace(/=/g, '&equals;');
+    txt = placeholderToBreak(txt);
+  }
+
+  return txt;
+};
+
+const breakToPlaceholder = s => {
+  return s.replace(/<br\s*\/?>/gi, '#br#');
+};
+
+const placeholderToBreak = s => {
+  return s.replace(/#br#/g, '<br/>');
+};
+
+export default {
+  getRows,
+  sanitizeText
+};