Reset unusedDelta on Onverscroll for residual values.

Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 7671 matching lines @@
     view->close();
 }
 
 class OverscrollWebViewClient : public FrameTestHelpers::TestWebViewClient {
 public:
     MOCK_METHOD4(didOverscroll, void(const WebFloatSize&, const WebFloatSize&, const WebFloatPoint&, const WebFloatSize&));
 };
 
 class WebFrameOverscrollTest : public WebFrameTest {
 protected:
-    WebGestureEvent generateEvent(WebInputEvent::Type type, int deltaX = 0, int deltaY = 0)
+    WebGestureEvent generateEvent(WebInputEvent::Type type, float deltaX = 0.0, float deltaY = 0.0)
     {
         WebGestureEvent event;
         event.type = type;
         event.x = 100;
         event.y = 100;
         if (type == WebInputEvent::GestureScrollUpdate) {
             event.data.scrollUpdate.deltaX = deltaX;
             event.data.scrollUpdate.deltaY = deltaY;
         }
         return event;
@@ skipping 214 matching lines @@
     EXPECT_CALL(client, didOverscroll(WebFloatSize(-10, 0), WebFloatSize(-20, -30), WebFloatPoint(33, 33), WebFloatSize()));
     ScrollUpdate(&webViewHelper, 30, 0);
     Mock::VerifyAndClearExpectations(&client);
 
     // Overscroll is not reported.
     EXPECT_CALL(client, didOverscroll(WebFloatSize(), WebFloatSize(), WebFloatPoint(33, 33), WebFloatSize())).Times(0);
     ScrollEnd(&webViewHelper);
     Mock::VerifyAndClearExpectations(&client);
 }
 
+TEST_F(WebFrameOverscrollTest, NoOverscrollForSmallvalues)
+{
+    OverscrollWebViewClient client;
+    registerMockedHttpURLLoad("overscroll/overscroll.html");
+    FrameTestHelpers::WebViewHelper webViewHelper;
+    webViewHelper.initializeAndLoad(m_baseURL + "overscroll/overscroll.html", true, 0, &client, configureAndroid);
+
+    ScrollBegin(&webViewHelper);
+    EXPECT_CALL(client, didOverscroll(WebFloatSize(0, -10.01), WebFloatSize(0, -10.01), WebFloatPoint(100, 100), WebFloatSize()));
+    ScrollUpdate(&webViewHelper, 0, 10.01);
+    Mock::VerifyAndClearExpectations(&client);

[majidvp, 2015/07/09 18:01:18]

I suggest adding a test to verify that the threshold value 0.1 is not reset.
This ensures that tests document the expected behaviour.

[majidvp, 2015/07/09 18:21:30]

What about this?

+
+    // For residual values overscrollDelta should be reset and didOverscroll shouldn't be called.
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollUpdate(&webViewHelper, 0, 0.09);
+    Mock::VerifyAndClearExpectations(&client);
+
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollUpdate(&webViewHelper, 0.09, 0.09);
+    Mock::VerifyAndClearExpectations(&client);
+
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollUpdate(&webViewHelper, 0.09, 0);
+    Mock::VerifyAndClearExpectations(&client);
+
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollUpdate(&webViewHelper, 0, -0.09);
+    Mock::VerifyAndClearExpectations(&client);
+
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollUpdate(&webViewHelper, -0.09, -0.09);
+    Mock::VerifyAndClearExpectations(&client);
+
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollUpdate(&webViewHelper, -0.09, 0);
+    Mock::VerifyAndClearExpectations(&client);
+
+    // Overscroll is not reported.
+    EXPECT_CALL(client, didOverscroll(_, _, _, _)).Times(0);
+    ScrollEnd(&webViewHelper);
+    Mock::VerifyAndClearExpectations(&client);
+}
+
 TEST_F(WebFrameOverscrollTest, ReportingLatestOverscrollForElasticOverscroll)
 {
     OverscrollWebViewClient client;
     registerMockedHttpURLLoad("overscroll/overscroll.html");
     FrameTestHelpers::WebViewHelper webViewHelper;
     webViewHelper.initializeAndLoad(m_baseURL + "overscroll/overscroll.html", true, 0, &client, configureAndroid);
 
     // On disabling ReportWheelOverscroll, overscroll is not reported on MouseWheel.
     webViewHelper.webView()->settings()->setReportWheelOverscroll(false);
     EXPECT_CALL(client, didOverscroll(WebFloatSize(), WebFloatSize(), WebFloatPoint(), WebFloatSize())).Times(0);
@@ skipping 18 matching lines @@
 
 TEST_F(WebFrameTest, MaxFramesDetach)
 {
     registerMockedHttpURLLoad("max-frames-detach.html");
     FrameTestHelpers::WebViewHelper webViewHelper;
     WebViewImpl* webViewImpl = webViewHelper.initializeAndLoad(m_baseURL + "max-frames-detach.html", true);
     webViewImpl->mainFrameImpl()->collectGarbage();
 }
 
 } // namespace blink