Convert some spell-checking layout tests to use unified text checker

third_party/WebKit/LayoutTests/editing/spelling/resources/util.js

Index: third_party/WebKit/LayoutTests/editing/spelling/resources/util.js
diff --git a/third_party/WebKit/LayoutTests/editing/spelling/resources/util.js b/third_party/WebKit/LayoutTests/editing/spelling/resources/util.js
index 5f2522041a6e988395220b6a8aa3b0883cb449b2..4f1c4d16a3eb84432140a26c5c973849730c9339 100644
--- a/third_party/WebKit/LayoutTests/editing/spelling/resources/util.js
+++ b/third_party/WebKit/LayoutTests/editing/spelling/resources/util.js
@@ -66,3 +66,32 @@ function typeText(elem, text)
         typeCharacterCommand(text[i]);
     }
 }
+
+function runNextStep(test, steps, assertions) {
+    if (!steps.length) {
+        test.done();
+        return;
+    }
+
+    var step = steps.shift();
+    var assertion = assertions.shift();
+
+    step();
+    step_timeout(() => {
+        test.step(() => assertion());
+        runNextStep(test, steps, assertions);
+    }, 50);
+}
+
+function runSpellingTest(steps, assertions, opt_title)
+{
+    var t = async_test(opt_title);
+    if (!window.internals) {
+        t.step(() => assert_unreached('internals is required for this test'));
+        t.done();
+        return;
+    }
+
+    internals.settings.setUnifiedTextCheckerEnabled(true);
+    runNextStep(t, steps, assertions);
+}