ShapeDetection: Holding all of mock service to prevent GC

third_party/WebKit/LayoutTests/shapedetection/resources/mock-facedetection.js

Index: third_party/WebKit/LayoutTests/shapedetection/resources/mock-facedetection.js
diff --git a/third_party/WebKit/LayoutTests/shapedetection/resources/mock-facedetection.js b/third_party/WebKit/LayoutTests/shapedetection/resources/mock-facedetection.js
index 1faf89f7727c4a8bcbeb293978e3c643e5d2693a..52dc0d8d0e98a2e4f7dd08adb3c3a42cd572493f 100644
--- a/third_party/WebKit/LayoutTests/shapedetection/resources/mock-facedetection.js
+++ b/third_party/WebKit/LayoutTests/shapedetection/resources/mock-facedetection.js
@@ -17,36 +17,42 @@ let mockFaceDetectionProviderReady = define(
       interfaces.addInterfaceOverrideForTesting(
           faceDetectionProvider.FaceDetectionProvider.name,
           handle => this.bindingSet_.addBinding(this, handle));
+
+      this.serviceArray_ = [];

[Ken Rockot(use gerrit already), 2017/05/03 16:48:54]

nit: how about "mockServiceInstances_" instead of "serviceArray_"?

+      this.buffer_data_ = [];
     }
 
     createFaceDetection(request, options) {
-      this.mock_service_ = new MockFaceDetection(request, options);
+      this.maxDetectedFaces_ = options.max_detected_faces;

[Ken Rockot(use gerrit already), 2017/05/03 16:48:54]

Doesn't this effectively cause the same problem as we have with the mock service
instances now? i.e. multiple tests may be using this provider object at the same
time and can thus trample the properties set here?

+      this.fastMode_ = options.fast_mode;
+
+      let mock_service = new MockFaceDetection(request, options, this);

[Ken Rockot(use gerrit already), 2017/05/03 16:48:54]

nit: Please either just delete this unnecessary line (inline the new at the
push() call) or fix the naming style to mockService

+      this.serviceArray_.push(mock_service);
     }
 
     getFrameData() {
-      return this.mock_service_.buffer_data_;
+      return this.buffer_data_;

[Ken Rockot(use gerrit already), 2017/05/03 16:48:54]

nit: While you're here, please fix the naming style to bufferData_.

     }
 
     getMaxDetectedFaces() {
-     return this.mock_service_.maxDetectedFaces_;
+     return this.maxDetectedFaces_;
     }
 
     getFastMode () {
-      return this.mock_service_.fastMode_;
+      return this.fastMode_;
     }
   }
 
   class MockFaceDetection {
-    constructor(request, options) {
-      this.maxDetectedFaces_ = options.max_detected_faces;
-      this.fastMode_ = options.fast_mode;
+    constructor(request, options, provider) {
+      this.provider_ = provider;
       this.binding_ = new bindings.Binding(faceDetection.FaceDetection, this,
                                            request);
     }
 
     detect(frame_data, width, height) {
       let receivedStruct = mojo.mapBuffer(frame_data, 0, width*height*4, 0);
-      this.buffer_data_ = new Uint32Array(receivedStruct.buffer);
+      this.provider_.buffer_data_ = new Uint32Array(receivedStruct.buffer);
       return Promise.resolve({
         result: {
           bounding_boxes: [