Ensure async selections after longpress activate the handles

ui/touch_selection/touch_selection_controller_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ui/touch_selection/touch_selection_controller.h"
 
 #include <vector>
 
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ skipping 557 matching lines @@
   // Selection movement does not currently trigger a separate event.
   EXPECT_THAT(GetAndResetEvents(), ElementsAre(SELECTION_MOVED));
   EXPECT_EQ(start_rect.bottom_left(), GetLastEventStart());
   EXPECT_EQ(end_rect.bottom_left(), GetLastEventEnd());
 
   ClearSelection();
   EXPECT_THAT(GetAndResetEvents(), ElementsAre(SELECTION_CLEARED));
   EXPECT_EQ(gfx::PointF(), GetLastEventStart());
 }
 
+TEST_F(TouchSelectionControllerTest, SelectionAllowsEmptyUpdateAfterLongPress) {
+  gfx::RectF start_rect(5, 5, 0, 10);
+  gfx::RectF end_rect(50, 5, 0, 10);
+  bool visible = true;
+
+  OnLongPressEvent();
+  EXPECT_THAT(GetAndResetEvents(), IsEmpty());
+
+  // There may be several empty updates after a longpress due to the
+  // asynchronous response. These empty updates should not prevent the selection
+  // handles from (eventually) activating.
+  ClearSelection();
+  EXPECT_THAT(GetAndResetEvents(), IsEmpty());
+
+  ClearSelection();
+  EXPECT_THAT(GetAndResetEvents(), IsEmpty());
+
+  ChangeSelection(start_rect, visible, end_rect, visible);
+  EXPECT_THAT(GetAndResetEvents(), ElementsAre(SELECTION_SHOWN));
+}
+
 TEST_F(TouchSelectionControllerTest, SelectionRepeatedLongPress) {
   gfx::RectF start_rect(5, 5, 0, 10);
   gfx::RectF end_rect(50, 5, 0, 10);
   bool visible = true;
 
   OnLongPressEvent();
   ChangeSelection(start_rect, visible, end_rect, visible);
   EXPECT_THAT(GetAndResetEvents(), ElementsAre(SELECTION_SHOWN));
   EXPECT_EQ(start_rect.bottom_left(), GetLastEventStart());
   EXPECT_EQ(end_rect.bottom_left(), GetLastEventEnd());
@@ skipping 431 matching lines @@
   // A point outside the rect should not be handled.
   EXPECT_FALSE(controller().WillHandleLongPressEvent(outer_point));
   EXPECT_THAT(GetAndResetEvents(), IsEmpty());
 
   // A point inside the rect should be handled.
   EXPECT_TRUE(controller().WillHandleLongPressEvent(inner_point));
   EXPECT_THAT(GetAndResetEvents(), ElementsAre(SELECTION_SHOWN));
 }
 
 }  // namespace ui