Clean up expectations for animation helper tests.

LayoutTests/animations/resources/animation-test-helpers.js

 /* This is the helper function to run animation tests:
 
 Test page requirements:
 - The body must contain an empty div with id "result"
 - Call this function directly from the <script> inside the test page
 
 Function parameters:
     expected [required]: an array of arrays defining a set of CSS properties that must have given values at specific times (see below)
     callbacks [optional]: a function to be executed immediately after animation starts;
                           or, an object in the form {time: function} containing functions to be
@@ skipping 335 matching lines @@
             }
         }
     } else {
         result = isCloseEnough(computedValue, expectedValue, tolerance);
     }
     return result;
 }
 
 function endTest()
 {
-    document.getElementById('result').innerHTML = result;
+    var resultElement = useResultElement ? document.getElementById('result') : document.documentElement;
+    resultElement.innerHTML = result;
 
     if (window.testRunner)
         testRunner.notifyDone();
 }
 
 function runChecksWithRAF(checks)
 {
     var finished = true;
     var time = performance.now() - animStartTime;
 
@@ skipping 23 matching lines @@
 }
 
 function startTest(checks)
 {
     if (hasPauseAnimationAPI)
         runChecksWithPauseAPI(checks);
     else
         runChecksWithRAF(checks);
 }
 
+var useResultElement = false;
 var result = "";
 var hasPauseAnimationAPI;
 var animStartTime;
 
 // FIXME: remove deprecatedEvent, disablePauseAnimationAPI and doPixelTest
 function runAnimationTest(expected, callbacks, deprecatedEvent, disablePauseAnimationAPI, doPixelTest)
 {
+    if (disablePauseAnimationAPI)
+        result += 'Warning this test is running in real-time and may be flaky.<br>';
     if (deprecatedEvent)
         throw 'Event argument is deprecated!';
     if (!expected)
         throw "Expected results are missing!";
 
     hasPauseAnimationAPI = 'internals' in window;
     if (disablePauseAnimationAPI)
         hasPauseAnimationAPI = false;
 
     var checks = {};
 
     if (typeof callbacks == 'function')
         checks[0] = [callbacks];
     else for (var time in callbacks) {
         timeMs = Math.round(time * 1000);
         checks[timeMs] = [callbacks[time]];
     }
 
     for (var i = 0; i < expected.length; i++) {
         var expectation = expected[i];
         var timeMs = Math.round(expectation[1] * 1000);
         if (!checks[timeMs])
             checks[timeMs] = [];
         checks[timeMs].push(checkExpectedValue.bind(null, expected, i));
     }
 
+    var doPixelTest = Boolean(doPixelTest);
+    useResultElement = doPixelTest;
+
     if (window.testRunner) {
-        if (!doPixelTest)
-            testRunner.dumpAsText();
+        testRunner.dumpAsText(doPixelTest);
         testRunner.waitUntilDone();
     }
 
     var started = false;
     document.addEventListener('webkitAnimationStart', function() {
         if (!started) {
             started = true;
             animStartTime = performance.now();
             // delay to give hardware animations a chance to start
             setTimeout(function() {
                 startTest(checks);
             }, 0);
         }
     }, false);
 }