Properly handle \r\n in JSXText (#1170)

Fixes #1168

src/printer.js

@@ -2757,7 +2757,7 @@ function printJSXChildren(path, options, print, jsxWhitespace) {
 
         if (/\S/.test(value)) {
           // treat each line of text as its own entity
-          value.split(/(\n\s*)/).forEach(line => {
+          value.split(/(\r?\n\s*)/).forEach(line => {
             const newlines = line.match(/\n/g);
             if (newlines) {
               children.push(hardline);

tests/jsx-newlines/__snapshots__/jsfmt.spec.js.snap

@@ -187,3 +187,14 @@ regression_extra_newline_2 = (
 );
 "
 `;
+
+exports[`windows.js 1`] = `
+"<div>
+Text
+</div>
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+<div>
+  Text
+</div>;
+"
+`;

tests/jsx-newlines/windows.js

@@ -0,0 +1,3 @@
+<div>
+Text
+</div>