ShapeDetection: Holding all of mock service to prevent GC

third_party/WebKit/LayoutTests/shapedetection/detection-HTMLCanvasElement.html

Index: third_party/WebKit/LayoutTests/shapedetection/detection-HTMLCanvasElement.html
diff --git a/third_party/WebKit/LayoutTests/shapedetection/detection-HTMLCanvasElement.html b/third_party/WebKit/LayoutTests/shapedetection/detection-HTMLCanvasElement.html
index f5f692ce20589a1744e057d39713e62428878d4e..161df617b40dbb7db7cd537eead8b2157527e0ae 100644
--- a/third_party/WebKit/LayoutTests/shapedetection/detection-HTMLCanvasElement.html
+++ b/third_party/WebKit/LayoutTests/shapedetection/detection-HTMLCanvasElement.html
@@ -7,14 +7,13 @@
 <script src="resources/mock-textdetection.js"></script>
 <script>
 
-var createTestForCanvasElement = function(createDetector,
-                                          createCanvas,
-                                          mockReady,
-                                          detectionResultTest) {
-  async_test(function(t) {
-
-    var img = new Image();
-    img.onload = function() {
+function detectShapeForCanvas(createDetector,
+                              createCanvas,
+                              mockReady,
+                              detectionResultTest) {
+  return new Promise(function(resolve, reject) {
+      var img = new Image();
+      img.onload = function() {
 
       var canvas = createCanvas();
       canvas.getContext("2d").drawImage(img, 0, 0);
@@ -34,14 +33,29 @@ var createTestForCanvasElement = function(createDetector,
         })
         .then(detectionResult => {
           detectionResultTest(detectionResult, theMock);
-          t.done();
+          resolve("Success");
         })
         .catch(error => {
           assert_unreached("Error during detect(canvas): " + error);
         });
-    }
+      }
 
-    img.src = "../media/content/greenbox.png";
+      img.src = "../media/content/greenbox.png";
+  });
+}
+
+var createTestForCanvasElement = function(createDetector,
+                                          createCanvas,
+                                          mockReady,
+                                          detectionResultTest) {
+  promise_test(function() {
+    return detectShapeForCanvas(createDetector,
+                                createCanvas,
+                                mockReady,
+                                detectionResultTest)
+        .then(function(result) {
+            assert_equals(result, "Success", "Detect 'Success'");
+        });
   });
 };