Reland "Added Fling Bubbling browsertests."

This is a reland of f24f12dd

This cl is using RenderFrameDeletedObserver to avoid crbug.com/889002
which is the cause of the crashes in flakiness dashboard:
https://chromium-swarm.appspot.com/task?id=409ddad025e7a610&refresh=10&show_raw=1


Original change's description:
> Added Fling Bubbling browsertests.
>
> The tests were initially landed in the following cl:
> https://chromium-review.googlesource.com/c/chromium/src/+/1278963
>
> The logic of the cl is re-landed in a separate cl(r599781) to give it
> more time to bake. This cl re-lands the browser tests after applying
> the following changes:
>
> 1- Addressed renaming nit.
> 2- Used MainThreadFrameObserver to make sure that compositor is synced
> after scrolling on main thread.
>
> Bug: 894703
> Change-Id: I25d6dbf7f216bbedecb6673d6c2819dcd1d82d55
> Reviewed-on: https://chromium-review.googlesource.com/c/1286875
> Reviewed-by: Charlie Reis <creis@chromium.org>
> Reviewed-by: Kevin McNee <mcnee@chromium.org>
> Commit-Queue: Sahel Sharify <sahel@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#600509}

Bug: 894703
Change-Id: I07b802b807c93beb684378e2fe18357fabf3ecbe
Reviewed-on: https://chromium-review.googlesource.com/c/1289515Reviewed-by: Charlie Reis <creis@chromium.org>
Commit-Queue: Sahel Sharify <sahel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#600931}

content/browser/renderer_host/input/fling_browsertest.cc

@@ -2,6 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+#include "build/build_config.h"
 #include "content/browser/renderer_host/input/synthetic_smooth_scroll_gesture.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/test/browser_test_utils.h"
@@ -74,6 +75,11 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
         shell()->web_contents()->GetRenderViewHost()->GetWidget());
   }
 
+  void SynchronizeThreads() {
+    MainThreadFrameObserver observer(GetWidgetHost());
+    observer.Wait();
+  }
+
   void LoadURL(const std::string& page_data) {
     const GURL data_url("data:text/html," + page_data);
     NavigateToURL(shell(), data_url);
@@ -84,25 +90,29 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
     base::string16 ready_title(base::ASCIIToUTF16("ready"));
     TitleWatcher watcher(shell()->web_contents(), ready_title);
     ignore_result(watcher.WaitAndGetTitle());
-
-    MainThreadFrameObserver main_thread_sync(host);
-    main_thread_sync.Wait();
+    SynchronizeThreads();
   }
 
   void LoadPageWithOOPIF() {
     // navigate main frame to URL.
     GURL main_url(embedded_test_server()->GetURL(
-        "a.com", "/frame_tree/page_with_positioned_frame.html"));
+        "a.com", "/frame_tree/scrollable_page_with_positioned_frame.html"));
     EXPECT_TRUE(NavigateToURL(shell(), main_url));
 
-    // Navigate oopif to URL.
     FrameTreeNode* root = static_cast<WebContentsImpl*>(shell()->web_contents())
                               ->GetFrameTree()
                               ->root();
     ASSERT_EQ(1U, root->child_count());
+
+    // Navigate oopif to URL.
     FrameTreeNode* iframe_node = root->child_at(0);
     GURL iframe_url(embedded_test_server()->GetURL("b.com", "/tall_page.html"));
-    NavigateFrameToURL(iframe_node, iframe_url);
+    {
+      RenderFrameDeletedObserver deleted_observer(
+          iframe_node->current_frame_host());
+      NavigateFrameToURL(iframe_node, iframe_url);
+      deleted_observer.WaitUntilDeleted();
+    }
 
     WaitForHitTestDataOrChildSurfaceReady(iframe_node->current_frame_host());
     FrameTreeVisualizer visualizer;
@@ -119,17 +129,29 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
         iframe_node->current_frame_host()->GetRenderWidgetHost()->GetView());
   }
 
-  void SimulateTouchscreenFling(RenderWidgetHostImpl* render_widget_host) {
+  void SimulateTouchscreenFling(
+      RenderWidgetHostImpl* render_widget_host,
+      RenderWidgetHostImpl* parent_render_widget_host = nullptr,
+      const gfx::Vector2dF& fling_velocity = gfx::Vector2dF(0.f, -2000.f)) {
     DCHECK(render_widget_host);
-    // Send a GSB to start scrolling sequence.
+    // Send a GSB to start scrolling sequence. In case of scroll bubbling wait
+    // for the parent to receive the GSB before sending the GFS.
+    auto input_msg_watcher =
+        parent_render_widget_host
+            ? std::make_unique<InputMsgWatcher>(
+                  parent_render_widget_host,
+                  blink::WebInputEvent::kGestureScrollBegin)
+            : std::make_unique<InputMsgWatcher>(
+                  render_widget_host,
+                  blink::WebInputEvent::kGestureScrollBegin);
     blink::WebGestureEvent gesture_scroll_begin(
         blink::WebGestureEvent::kGestureScrollBegin,
         blink::WebInputEvent::kNoModifiers, ui::EventTimeForNow());
     gesture_scroll_begin.SetSourceDevice(blink::kWebGestureDeviceTouchscreen);
     gesture_scroll_begin.data.scroll_begin.delta_hint_units =
         blink::WebGestureEvent::ScrollUnits::kPrecisePixels;
-    gesture_scroll_begin.data.scroll_begin.delta_x_hint = 0.f;
-    gesture_scroll_begin.data.scroll_begin.delta_y_hint = -5.f;
+    gesture_scroll_begin.data.scroll_begin.delta_x_hint = fling_velocity.x();
+    gesture_scroll_begin.data.scroll_begin.delta_y_hint = fling_velocity.y();
     const gfx::PointF scroll_location_in_widget(1, 1);
     const gfx::PointF scroll_location_in_root =
         child_view_ ? child_view_->TransformPointToRootCoordSpaceF(
@@ -142,26 +164,39 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
     gesture_scroll_begin.SetPositionInWidget(scroll_location_in_widget);
     gesture_scroll_begin.SetPositionInScreen(scroll_location_in_screen);
     render_widget_host->ForwardGestureEvent(gesture_scroll_begin);
+    input_msg_watcher->GetAckStateWaitIfNecessary();
 
     //  Send a GFS.
     blink::WebGestureEvent gesture_fling_start(
         blink::WebGestureEvent::kGestureFlingStart,
         blink::WebInputEvent::kNoModifiers, ui::EventTimeForNow());
     gesture_fling_start.SetSourceDevice(blink::kWebGestureDeviceTouchscreen);
-    gesture_fling_start.data.fling_start.velocity_x = 0.f;
-    gesture_fling_start.data.fling_start.velocity_y = -2000.f;
+    gesture_fling_start.data.fling_start.velocity_x = fling_velocity.x();
+    gesture_fling_start.data.fling_start.velocity_y = fling_velocity.y();
     gesture_fling_start.SetPositionInWidget(scroll_location_in_widget);
     gesture_fling_start.SetPositionInScreen(scroll_location_in_screen);
     render_widget_host->ForwardGestureEvent(gesture_fling_start);
   }
 
-  void SimulateTouchpadFling(RenderWidgetHostImpl* render_widget_host) {
+  void SimulateTouchpadFling(
+      RenderWidgetHostImpl* render_widget_host,
+      RenderWidgetHostImpl* parent_render_widget_host = nullptr,
+      const gfx::Vector2dF& fling_velocity = gfx::Vector2dF(0.f, -2000.f)) {
     DCHECK(render_widget_host);
-    // Send a wheel event to start scrolling sequence.
-    auto input_msg_watcher = std::make_unique<InputMsgWatcher>(
-        GetWidgetHost(), blink::WebInputEvent::kMouseWheel);
+    // Send a wheel event to start scrolling sequence. In case of scroll
+    // bubbling wait for the parent to receive the GSB before sending the GFS.
+    auto input_msg_watcher =
+        parent_render_widget_host
+            ? std::make_unique<InputMsgWatcher>(
+                  parent_render_widget_host,
+                  blink::WebInputEvent::kGestureScrollBegin)
+            : std::make_unique<InputMsgWatcher>(
+                  render_widget_host,
+                  blink::WebInputEvent::kGestureScrollBegin);
     blink::WebMouseWheelEvent wheel_event =
-        SyntheticWebMouseWheelEventBuilder::Build(10, 10, 0, -53, 0, true);
+        SyntheticWebMouseWheelEventBuilder::Build(
+            10, 10, fling_velocity.x() / 1000, fling_velocity.y() / 1000, 0,
+            true);
     wheel_event.phase = blink::WebMouseWheelEvent::kPhaseBegan;
     const gfx::PointF position_in_widget(1, 1);
     const gfx::PointF position_in_root =
@@ -175,15 +210,15 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
     wheel_event.SetPositionInWidget(position_in_widget);
     wheel_event.SetPositionInScreen(position_in_screen);
     render_widget_host->ForwardWheelEvent(wheel_event);
-    input_msg_watcher->WaitForAck();
+    input_msg_watcher->GetAckStateWaitIfNecessary();
 
     //  Send a GFS.
     blink::WebGestureEvent gesture_fling_start(
         blink::WebGestureEvent::kGestureFlingStart,
         blink::WebInputEvent::kNoModifiers, ui::EventTimeForNow());
     gesture_fling_start.SetSourceDevice(blink::kWebGestureDeviceTouchpad);
-    gesture_fling_start.data.fling_start.velocity_x = 0.f;
-    gesture_fling_start.data.fling_start.velocity_y = -2000.f;
+    gesture_fling_start.data.fling_start.velocity_x = fling_velocity.x();
+    gesture_fling_start.data.fling_start.velocity_y = fling_velocity.y();
     gesture_fling_start.SetPositionInWidget(position_in_widget);
     gesture_fling_start.SetPositionInScreen(position_in_screen);
     render_widget_host->ForwardGestureEvent(gesture_fling_start);
@@ -212,25 +247,36 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
     run_loop.Run();
   }
 
-  void WaitForChildScroll() {
-    FrameTreeNode* root = static_cast<WebContentsImpl*>(shell()->web_contents())
-                              ->GetFrameTree()
-                              ->root();
-    ASSERT_EQ(1U, root->child_count());
-    FrameTreeNode* iframe_node = root->child_at(0);
-    int scroll_top = EvalJs(iframe_node->current_frame_host(), "window.scrollY")
-                         .ExtractDouble();
+  void WaitForFrameScroll(FrameTreeNode* frame_node,
+                          int target_scroll_offset = 100,
+                          bool upward = false) {
+    DCHECK(frame_node);
+    double scroll_top =
+        EvalJs(frame_node->current_frame_host(), "window.scrollY")
+            .ExtractDouble();
     // scrollTop > 0 is not enough since the first progressFling is called from
-    // FlingController::ProcessGestureFlingStart. Wait for scrollTop to exceed
-    // 100 pixels to make sure that ProgressFling has been called through
-    // FlingScheduler at least once.
-    while (scroll_top < 100) {
+    // FlingController::ProcessGestureFlingStart. Wait for scrollTop to reach
+    // target_scroll_offset to make sure that ProgressFling has been called
+    // through FlingScheduler at least once.
+    while ((upward && scroll_top > target_scroll_offset) ||
+           (!upward && scroll_top < target_scroll_offset)) {
       GiveItSomeTime();
-      scroll_top = EvalJs(iframe_node->current_frame_host(), "window.scrollY")
+      scroll_top = EvalJs(frame_node->current_frame_host(), "window.scrollY")
                        .ExtractDouble();
     }
   }
 
+  FrameTreeNode* GetRootNode() {
+    return static_cast<WebContentsImpl*>(shell()->web_contents())
+        ->GetFrameTree()
+        ->root();
+  }
+
+  FrameTreeNode* GetChildNode() {
+    FrameTreeNode* root = GetRootNode();
+    return root->child_at(0);
+  }
+
   std::unique_ptr<base::RunLoop> run_loop_;
   RenderWidgetHostViewBase* child_view_ = nullptr;
   RenderWidgetHostViewBase* root_view_ = nullptr;
@@ -239,6 +285,10 @@ class BrowserSideFlingBrowserTest : public ContentBrowserTest {
   DISALLOW_COPY_AND_ASSIGN(BrowserSideFlingBrowserTest);
 };
 
+// On Mac we don't have any touchscreen/touchpad fling events (GFS/GFC).
+// Instead, the OS keeps sending wheel events when the user lifts their fingers
+// from touchpad.
+#if !defined(OS_MACOSX)
 IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest, TouchscreenFling) {
   LoadURL(kBrowserFlingDataURL);
   SimulateTouchscreenFling(GetWidgetHost());
@@ -257,8 +307,7 @@ IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
   GURL first_url(embedded_test_server()->GetURL(
       "b.a.com", "/scrollable_page_with_iframe.html"));
   EXPECT_TRUE(NavigateToURL(shell(), first_url));
-  MainThreadFrameObserver main_thread_sync1(GetWidgetHost());
-  main_thread_sync1.Wait();
+  SynchronizeThreads();
   SimulateTouchscreenFling(GetWidgetHost());
   WaitForScroll();
 
@@ -266,8 +315,7 @@ IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
   GURL second_url(
       embedded_test_server()->GetURL("a.com", "/scrollable_page.html"));
   NavigateToURL(shell(), second_url);
-  MainThreadFrameObserver main_thread_sync2(GetWidgetHost());
-  main_thread_sync2.Wait();
+  SynchronizeThreads();
 
   // Wait for 100ms. Then check that the second page has not scrolled.
   GiveItSomeTime(100);
@@ -281,23 +329,89 @@ IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
 IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest, TouchscreenFlingInOOPIF) {
   LoadPageWithOOPIF();
   SimulateTouchscreenFling(child_view_->host());
-  WaitForChildScroll();
+  WaitForFrameScroll(GetChildNode());
 }
 IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest, TouchpadFlingInOOPIF) {
   LoadPageWithOOPIF();
-  SimulateTouchscreenFling(child_view_->host());
-  WaitForChildScroll();
+  SimulateTouchpadFling(child_view_->host());
+  WaitForFrameScroll(GetChildNode());
+}
+IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
+                       TouchscreenFlingBubblesFromOOPIF) {
+  LoadPageWithOOPIF();
+  // Scroll the parent down so that it is scrollable upward.
+  EXPECT_TRUE(
+      ExecJs(GetRootNode()->current_frame_host(), "window.scrollTo(0, 20)"));
+  // We expect to have window.scrollY == 20 after scrolling but with zoom for
+  // dsf enabled on android we get window.scrollY == 19 (see
+  // https://crbug.com/891860).
+  WaitForFrameScroll(GetRootNode(), 19);
+  SynchronizeThreads();
+
+  // Fling and wait for the parent to scroll upward.
+  gfx::Vector2d fling_velocity(0, 2000);
+  SimulateTouchscreenFling(child_view_->host(), GetWidgetHost(),
+                           fling_velocity);
+  WaitForFrameScroll(GetRootNode(), 15, true /* upward */);
+}
+
+// Flaky, probably because of https://crbug.com/892656
+IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
+                       DISABLED_TouchpadFlingBubblesFromOOPIF) {
+  LoadPageWithOOPIF();
+  // Scroll the parent down so that it is scrollable upward.
+  EXPECT_TRUE(
+      ExecJs(GetRootNode()->current_frame_host(), "window.scrollTo(0, 20)"));
+  // We expect to have window.scrollY == 20 after scrolling but with zoom for
+  // dsf enabled on android we get window.scrollY == 19 (see
+  // https://crbug.com/891860).
+  WaitForFrameScroll(GetRootNode(), 19);
+  SynchronizeThreads();
+
+  // Fling and wait for the parent to scroll upward.
+  gfx::Vector2d fling_velocity(0, 2000);
+  SimulateTouchpadFling(child_view_->host(), GetWidgetHost(), fling_velocity);
+  WaitForFrameScroll(GetRootNode(), 15, true /* upward */);
+}
+IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest, GFCGetsBubbledFromOOPIF) {
+  LoadPageWithOOPIF();
+  // Scroll the parent down so that it is scrollable upward.
+  EXPECT_TRUE(
+      ExecJs(GetRootNode()->current_frame_host(), "window.scrollTo(0, 20)"));
+  // We expect to have window.scrollY == 20 after scrolling but with zoom for
+  // dsf enabled on android we get window.scrollY == 19 (see
+  // https://crbug.com/891860).
+  WaitForFrameScroll(GetRootNode(), 19);
+  SynchronizeThreads();
+
+  // Fling and wait for the parent to scroll upward.
+  gfx::Vector2d fling_velocity(0, 2000);
+  SimulateTouchscreenFling(child_view_->host(), GetWidgetHost(),
+                           fling_velocity);
+  WaitForFrameScroll(GetRootNode(), 15, true /* upward */);
+
+  // Send a GFC to the child and wait for it to get bubbled.
+  auto input_msg_watcher = std::make_unique<InputMsgWatcher>(
+      GetWidgetHost(), blink::WebInputEvent::kGestureFlingCancel);
+  blink::WebGestureEvent gesture_fling_cancel(
+      blink::WebGestureEvent::kGestureFlingCancel,
+      blink::WebInputEvent::kNoModifiers, ui::EventTimeForNow());
+  gesture_fling_cancel.SetSourceDevice(blink::kWebGestureDeviceTouchscreen);
+
+  const gfx::PointF location_in_widget(1, 1);
+  const gfx::PointF location_in_root =
+      child_view_->TransformPointToRootCoordSpaceF(location_in_widget);
+  const gfx::PointF location_in_screen =
+      location_in_root + root_view_->GetViewBounds().OffsetFromOrigin();
+  gesture_fling_cancel.SetPositionInWidget(location_in_widget);
+  gesture_fling_cancel.SetPositionInScreen(location_in_screen);
+  child_view_->host()->ForwardGestureEvent(gesture_fling_cancel);
+  input_msg_watcher->GetAckStateWaitIfNecessary();
 }
 
-// Disabled on MacOS because it doesn't support touchscreen scroll.
-#if defined(OS_MACOSX)
-#define MAYBE_ScrollEndGeneratedForFilteredFling \
-  DISABLED_ScrollEndGeneratedForFilteredFling
-#else
 // Flaky, see https://crbug.com/850455
 #define MAYBE_ScrollEndGeneratedForFilteredFling \
   DISABLED_ScrollEndGeneratedForFilteredFling
-#endif
 IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
                        MAYBE_ScrollEndGeneratedForFilteredFling) {
   LoadURL(kTouchActionFilterDataURL);
@@ -348,5 +462,6 @@ IN_PROC_BROWSER_TEST_F(BrowserSideFlingBrowserTest,
   EXPECT_EQ(InputEventAckSource::BROWSER,
             scroll_end_watcher->last_event_ack_source());
 }
+#endif  // !defined(OS_MACOSX)
 
 }  // namespace content