OverscrollController consumes scroll updates only during gesture-nav.

content/browser/web_contents/web_contents_view_aura_browsertest.cc

Index: content/browser/web_contents/web_contents_view_aura_browsertest.cc
diff --git a/content/browser/web_contents/web_contents_view_aura_browsertest.cc b/content/browser/web_contents/web_contents_view_aura_browsertest.cc
index bdd74817ddb5f5525b0e86487c98f4710a2e3474..f7a8f615bd114fa9f07d68b3cb0c6d0c7e97d23e 100644
--- a/content/browser/web_contents/web_contents_view_aura_browsertest.cc
+++ b/content/browser/web_contents/web_contents_view_aura_browsertest.cc
@@ -18,7 +18,10 @@
 #include "content/browser/renderer_host/render_widget_host_view_aura.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/browser/web_contents/web_contents_view.h"
+#include "content/common/input/synthetic_web_input_event_builders.h"
+#include "content/common/input_messages.h"
 #include "content/common/view_messages.h"
+#include "content/public/browser/browser_message_filter.h"
 #include "content/public/browser/render_frame_host.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/common/content_switches.h"
@@ -32,9 +35,24 @@
 #include "ui/aura/window_tree_host.h"
 #include "ui/compositor/scoped_animation_duration_scale_mode.h"
 #include "ui/events/event_processor.h"
+#include "ui/events/event_switches.h"
 #include "ui/events/event_utils.h"
 #include "ui/events/test/event_generator.h"
 
+namespace {
+
+void GiveItSomeTime() {
+  base::RunLoop run_loop;
+  base::MessageLoop::current()->PostDelayedTask(
+      FROM_HERE,
+      run_loop.QuitClosure(),
+      base::TimeDelta::FromMillisecondsD(0.001));

[tdresser, 2014/08/15 23:10:32]

0.001ms is obviously a terrible value, I'm only using it to reduce the chance
that flaky behavior will pass the trybots.

+  run_loop.Run();
+}
+
+}  //namespace
+
+
 namespace content {
 
 // This class keeps track of the RenderViewHost whose screenshot was captured.
@@ -127,6 +145,55 @@ class NavigationWatcher : public WebContentsObserver {
   DISALLOW_COPY_AND_ASSIGN(NavigationWatcher);
 };
 
+class InputEventMessageFilterWaitsForAcks : public BrowserMessageFilter {
+ public:
+  InputEventMessageFilterWaitsForAcks()
+      : BrowserMessageFilter(InputMsgStart),
+        type_(blink::WebInputEvent::Undefined),
+        state_(INPUT_EVENT_ACK_STATE_UNKNOWN) {}
+
+  void WaitForAck(blink::WebInputEvent::Type type) {
+    base::RunLoop run_loop;
+    base::AutoReset<base::Closure> reset_quit(&quit_, run_loop.QuitClosure());
+    base::AutoReset<blink::WebInputEvent::Type> reset_type(&type_, type);
+    run_loop.Run();
+  }
+
+  InputEventAckState last_ack_state() const { return state_; }
+
+ protected:
+  virtual ~InputEventMessageFilterWaitsForAcks() {}
+
+ private:
+  void ReceivedEventAck(blink::WebInputEvent::Type type,
+                        InputEventAckState state) {
+    if (type_ == type) {
+      state_ = state;
+      quit_.Run();
+    }
+  }
+
+  // BrowserMessageFilter:
+  virtual bool OnMessageReceived(const IPC::Message& message) OVERRIDE {
+    if (message.type() == InputHostMsg_HandleInputEvent_ACK::ID) {
+      InputHostMsg_HandleInputEvent_ACK::Param params;
+      InputHostMsg_HandleInputEvent_ACK::Read(&message, &params);
+      blink::WebInputEvent::Type type = params.a.type;
+      InputEventAckState ack = params.a.state;
+      BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+          base::Bind(&InputEventMessageFilterWaitsForAcks::ReceivedEventAck,
+                     this, type, ack));
+    }
+    return false;
+  }
+
+  base::Closure quit_;
+  blink::WebInputEvent::Type type_;
+  InputEventAckState state_;
+
+  DISALLOW_COPY_AND_ASSIGN(InputEventMessageFilterWaitsForAcks);
+};
+
 class WebContentsViewAuraTest : public ContentBrowserTest {
  public:
   WebContentsViewAuraTest()
@@ -156,6 +223,11 @@ class WebContentsViewAuraTest : public ContentBrowserTest {
     controller->SetScreenshotManager(screenshot_manager_);
   }
 
+  virtual void SetUpCommandLine(CommandLine* cmd) OVERRIDE {
+    cmd->AppendSwitchASCII(switches::kTouchEvents,
+                           switches::kTouchEventsEnabled);
+  }
+
   void TestOverscrollNavigation(bool touch_handler) {
     ASSERT_NO_FATAL_FAILURE(
         StartTestWithPage("files/overscroll_navigation.html"));
@@ -256,14 +328,62 @@ class WebContentsViewAuraTest : public ContentBrowserTest {
     return index;
   }
 
+  int ExecuteScriptAndExtractInt(const std::string& script) {
+    int value = 0;
+    EXPECT_TRUE(content::ExecuteScriptAndExtractInt(
+        shell()->web_contents(),
+        "domAutomationController.send(" + script + ")",
+        &value));
+    return value;
+  }
+
+  RenderViewHost* GetRenderViewHost() const {
+    RenderViewHost* const rvh = shell()->web_contents()->GetRenderViewHost();
+    CHECK(rvh);
+    return rvh;
+  }
+
+  RenderWidgetHostImpl* GetRenderWidgetHost() const {
+    RenderWidgetHostImpl* const rwh =
+        RenderWidgetHostImpl::From(shell()
+                                       ->web_contents()
+                                       ->GetRenderWidgetHostView()
+                                       ->GetRenderWidgetHost());
+    CHECK(rwh);
+    return rwh;
+  }
+
+  RenderWidgetHostViewBase* GetRenderWidgetHostView() const {
+    return static_cast<RenderWidgetHostViewBase*>(
+        GetRenderViewHost()->GetView());
+  }
+
+  InputEventMessageFilterWaitsForAcks* filter() {
+    return filter_.get();
+  }
+
+  void WaitAFrame() {
+    uint32 frame = GetRenderWidgetHostView()->RendererFrameNumber();
+    while (!GetRenderWidgetHost()->ScheduleComposite())
+      GiveItSomeTime();
+    while (GetRenderWidgetHostView()->RendererFrameNumber() == frame)
+      GiveItSomeTime();
+  }
+
  protected:
   ScreenshotTracker* screenshot_manager() { return screenshot_manager_; }
   void set_min_screenshot_interval(int interval_ms) {
     screenshot_manager_->SetScreenshotInterval(interval_ms);
   }
 
+  void AddInputEventMessageFilter() {
+    filter_ = new InputEventMessageFilterWaitsForAcks();
+    GetRenderWidgetHost()->GetProcess()->AddFilter(filter_);
+  }
+
  private:
   ScreenshotTracker* screenshot_manager_;
+  scoped_refptr<InputEventMessageFilterWaitsForAcks> filter_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsViewAuraTest);
 };
@@ -747,4 +867,90 @@ IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest, WebContentsViewReparent) {
   EXPECT_TRUE(rwhva->has_snapped_to_boundary());
 }
 
+// Tests that touch moves are not throttled when performing a scroll gesture on
+// a non-scrollable area, except during gesture-nav.
+IN_PROC_BROWSER_TEST_F(WebContentsViewAuraTest,
+                       OverscrollNavigationTouchThrottling) {
+  ASSERT_NO_FATAL_FAILURE(
+      StartTestWithPage("files/overscroll_navigation.html"));
+
+  AddInputEventMessageFilter();
+
+  WebContentsImpl* web_contents =
+      static_cast<WebContentsImpl*>(shell()->web_contents());
+  aura::Window* content = web_contents->GetContentNativeView();
+  gfx::Rect bounds = content->GetBoundsInRootWindow();
+  const int dx = 20;
+
+  ExecuteSyncJSFunction(web_contents->GetMainFrame(),
+                        "install_touchmove_handler()");
+
+  WaitAFrame();

[tdresser, 2014/08/15 23:10:32]

Dana, these WaitAFrame() calls are obviously terrible, with the current
implementation of WaitAFrame(). I'm not sure what else to wait on though. Just
waiting on the events acks doesn't do the trick in many cases. Is there a better
way to wait until the next frame?

+
+  for (int navigated = 0; navigated <= 1; ++navigated) {
+    if (navigated) {
+      ExecuteSyncJSFunction(web_contents->GetMainFrame(), "navigate_next()");
+      ExecuteSyncJSFunction(web_contents->GetMainFrame(),
+                            "reset_touchmove_count()");
+    }
+    // Send touch press.
+    SyntheticWebTouchEvent touch;
+    touch.PressPoint(bounds.x() + 2, bounds.y() + 10);
+    GetRenderWidgetHost()->ForwardTouchEventWithLatencyInfo(touch,
+                                                            ui::LatencyInfo());
+    filter()->WaitForAck(blink::WebInputEvent::TouchStart);
+    // Assert on the ack, because we'll end up waiting for acks that will never
+    // come if this is not true.
+    ASSERT_EQ(INPUT_EVENT_ACK_STATE_NOT_CONSUMED, filter()->last_ack_state());
+
+    // Send first touch move, and then a scroll begin.
+    touch.MovePoint(0, bounds.x() + 20 + 1 * dx, bounds.y() + 100);
+    GetRenderWidgetHost()->ForwardTouchEventWithLatencyInfo(touch,
+                                                            ui::LatencyInfo());
+    filter()->WaitForAck(blink::WebInputEvent::TouchMove);
+    ASSERT_EQ(INPUT_EVENT_ACK_STATE_NOT_CONSUMED, filter()->last_ack_state());
+
+    blink::WebGestureEvent scroll_begin =
+        SyntheticWebGestureEventBuilder::BuildScrollBegin(1, 1);
+    GetRenderWidgetHost()->ForwardGestureEventWithLatencyInfo(
+        scroll_begin, ui::LatencyInfo());
+    // Scroll begin ignores ack disposition, so don't wait for the ack.
+    //    GiveItSomeTime();
+    WaitAFrame();
+
+    // First touchmove already sent, start at 2.
+    for (int i = 2; i <= 10; ++i) {
+      // Send a touch move, followed by a scroll update
+      touch.MovePoint(0, bounds.x() + 20 + i * dx, bounds.y() + 100);
+      GetRenderWidgetHost()->ForwardTouchEventWithLatencyInfo(
+          touch, ui::LatencyInfo());
+      WaitAFrame();
+
+      blink::WebGestureEvent scroll_update =
+          SyntheticWebGestureEventBuilder::BuildScrollUpdate(dx, 5, 0);
+
+      GetRenderWidgetHost()->ForwardGestureEventWithLatencyInfo(
+          scroll_update, ui::LatencyInfo());
+
+      WaitAFrame();
+    }
+
+    touch.ReleasePoint(0);
+    GetRenderWidgetHost()->ForwardTouchEventWithLatencyInfo(touch,
+                                                            ui::LatencyInfo());
+    WaitAFrame();
+
+    blink::WebGestureEvent scroll_end;
+    scroll_end.type = blink::WebInputEvent::GestureScrollEnd;
+    GetRenderWidgetHost()->ForwardGestureEventWithLatencyInfo(
+        scroll_end, ui::LatencyInfo());
+    WaitAFrame();
+
+    if (!navigated)
+      EXPECT_EQ(10, ExecuteScriptAndExtractInt("touchmoveCount"));
+    else
+      EXPECT_GT(10, ExecuteScriptAndExtractInt("touchmoveCount"));
+  }
+}
+
 }  // namespace content