Move check for gesture end events out of RootViewTargeter

Instead of returning a NULL target for a ET_GESTURE_END
in the case where no default gesture handler has been
established, prevent processing in
RootView::OnEventProcessingStarted() by marking the
event as handled.

BUG=417771
TEST=ViewTargeterTest.ViewTargeterForGestureEvents changed,
     WidgetTest.GestureEndEvents changed,
     WidgetTest.GestureEventsNotProcessed changed,
     WidgetTest.DisabledGestureEventTarget changed

Review URL: https://codereview.chromium.org/619183002

Cr-Commit-Position: refs/heads/master@{#297897}

ui/views/view_targeter_unittest.cc

@@ -343,8 +343,7 @@ TEST_F(ViewTargeterTest, ViewTargeterForGestureEvents) {
   EXPECT_EQ(grandchild, targeter->FindTargetForEvent(root_view, &scroll_begin));
 
   // If no default gesture handler is currently set, GESTURE_END events
-  // should never be targeted or re-targeted to any View.
-  EXPECT_EQ(NULL, targeter->FindTargetForEvent(root_view, &end));
+  // should never be re-targeted to any View.
   EXPECT_EQ(NULL, targeter->FindNextBestTarget(NULL, &end));
   EXPECT_EQ(NULL, targeter->FindNextBestTarget(child, &end));
 }

ui/views/widget/root_view.cc

@@ -261,10 +261,12 @@ void RootView::OnEventProcessingStarted(ui::Event* event) {
     return;
   }
 
-  // Do not process ui::ET_GESTURE_END events which do not correspond to the
-  // removal of the final touch point.
+  // Do not process ui::ET_GESTURE_END events if they do not correspond to the
+  // removal of the final touch point or if no gesture handler has already
+  // been set.
   if (gesture_event->type() == ui::ET_GESTURE_END &&
-      gesture_event->details().touch_points() > 1) {
+      (gesture_event->details().touch_points() > 1 ||
+       !gesture_handler_)) {
     event->SetHandled();
     return;
   }

ui/views/widget/root_view_targeter.cc

@@ -31,13 +31,6 @@ View* RootViewTargeter::FindTargetForGestureEvent(
     return root_view_->gesture_handler_;
   }
 
-  // If no default gesture handler has already been set, do not perform any
-  // targeting for a ET_GESTURE_END event.
-  // TODO(tdanderson): This check belongs in
-  //                   RootView::OnEventProcessingStarted() instead of here.
-  if (gesture.type() == ui::ET_GESTURE_END)
-    return NULL;
-
   // If rect-based targeting is enabled, use the gesture's bounding box to
   // determine the target. Otherwise use the center point of the gesture's
   // bounding box to determine the target.

ui/views/widget/widget_unittest.cc

@@ -1992,12 +1992,10 @@ TEST_F(WidgetTest, GestureEndEvents) {
   widget->Show();
 
   // If no gesture handler is set, a ui::ET_GESTURE_END event should not set
-  // the gesture handler and the event should remain unhandled because the
-  // handle mode of |view| indicates that events should not be consumed.
+  // the gesture handler.
   EXPECT_EQ(NULL, GetGestureHandler(root_view));
   GestureEventForTest end(ui::ET_GESTURE_END, 15, 15);
   widget->OnGestureEvent(&end);
-  EXPECT_FALSE(end.handled());
   EXPECT_EQ(NULL, GetGestureHandler(root_view));
 
   // Change the handle mode of |view| to indicate that it would like
@@ -2091,6 +2089,22 @@ TEST_F(WidgetTest, GestureEventsNotProcessed) {
   v3->ResetCounts();
   v4->ResetCounts();
 
+  // ui::ET_GESTURE_END events should not be seen by any view when there is
+  // no default gesture handler set, but they should be marked as handled by
+  // OnEventProcessingStarted().
+  GestureEventForTest end(ui::ET_GESTURE_END, 5, 5);
+  widget->OnGestureEvent(&end);
+  EXPECT_EQ(0, v1->GetEventCount(ui::ET_GESTURE_END));
+  EXPECT_EQ(0, v2->GetEventCount(ui::ET_GESTURE_END));
+  EXPECT_EQ(0, v3->GetEventCount(ui::ET_GESTURE_END));
+  EXPECT_EQ(0, v4->GetEventCount(ui::ET_GESTURE_END));
+  EXPECT_EQ(NULL, GetGestureHandler(root_view));
+  EXPECT_TRUE(end.handled());
+  v1->ResetCounts();
+  v2->ResetCounts();
+  v3->ResetCounts();
+  v4->ResetCounts();
+
   // ui::ET_GESTURE_END events not corresponding to the release of the
   // final touch point should never be seen by any view, but they should
   // be marked as handled by OnEventProcessingStarted().
@@ -2548,23 +2562,6 @@ TEST_F(WidgetTest, DisabledGestureEventTarget) {
   v3->set_handle_mode(EventCountView::CONSUME_EVENTS);
   v3->SetEnabled(false);
 
-  // No gesture handler is set in the root view, so it should remain unset
-  // after a GESTURE_END. GESTURE_END events are not dispatched unless
-  // a gesture handler is already set in the root view, so none of the
-  // views should see this event and it should not be marked as handled.
-  GestureEventForTest end(ui::ET_GESTURE_END, 5, 5);
-  widget->OnGestureEvent(&end);
-  EXPECT_EQ(0, v1->GetEventCount(ui::ET_GESTURE_END));
-  EXPECT_EQ(0, v2->GetEventCount(ui::ET_GESTURE_END));
-  EXPECT_EQ(0, v3->GetEventCount(ui::ET_GESTURE_END));
-  EXPECT_EQ(0, v4->GetEventCount(ui::ET_GESTURE_END));
-  EXPECT_EQ(NULL, GetGestureHandler(root_view));
-  EXPECT_FALSE(end.handled());
-  v1->ResetCounts();
-  v2->ResetCounts();
-  v3->ResetCounts();
-  v4->ResetCounts();
-
   // No gesture handler is set in the root view. In this case the tap event
   // should be dispatched only to |v4|, the gesture handler should be set to
   // |v3|, and the event should be marked as handled.
@@ -2597,7 +2594,7 @@ TEST_F(WidgetTest, DisabledGestureEventTarget) {
 
   // A GESTURE_END should reset the default gesture handler to NULL. It should
   // also not be dispatched to |v3| but still marked as handled.
-  end = GestureEventForTest(ui::ET_GESTURE_END, 5, 5);
+  GestureEventForTest end(ui::ET_GESTURE_END, 5, 5);
   widget->OnGestureEvent(&end);
   EXPECT_EQ(0, v1->GetEventCount(ui::ET_GESTURE_END));
   EXPECT_EQ(0, v2->GetEventCount(ui::ET_GESTURE_END));