Show Overlay Scrollbar when GestureScrollUpdate

cc/trees/layer_tree_host_impl_unittest.cc

 // Copyright 2011 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 "cc/trees/layer_tree_host_impl.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <cmath>
@@ skipping 2719 matching lines @@
     host_impl_->active_tree()->BuildPropertyTreesForTesting();
     host_impl_->active_tree()->DidBecomeActive();
     DrawFrame();
   }
 
   void RunTest(LayerTreeSettings::ScrollbarAnimator animator) {
     LayerTreeSettings settings = DefaultSettings();
     settings.scrollbar_animator = animator;
     settings.scrollbar_fade_in_delay = base::TimeDelta::FromMilliseconds(20);
     settings.scrollbar_fade_out_delay = base::TimeDelta::FromMilliseconds(20);
+    settings.scrollbar_fade_out_resize_delay =
+        base::TimeDelta::FromMilliseconds(20);
     settings.scrollbar_fade_out_duration =
         base::TimeDelta::FromMilliseconds(20);
 
     // If no animator is set, scrollbar won't show and no animation is expected.
     bool expecting_animations = animator != LayerTreeSettings::NO_ANIMATOR;
 
     SetupLayers(settings);
 
     base::TimeTicks fake_now = base::TimeTicks::Now();
 
@@ skipping 13 matching lines @@
 
     // If no scroll happened during a scroll gesture, it should have no effect.
     host_impl_->ScrollBegin(BeginState(gfx::Point()).get(),
                             InputHandler::WHEEL);
     host_impl_->ScrollEnd(EndState().get());
     EXPECT_FALSE(did_request_next_frame_);
     EXPECT_FALSE(did_request_redraw_);
     EXPECT_EQ(base::TimeDelta(), requested_animation_delay_);
     EXPECT_TRUE(animation_task_.Equals(base::Closure()));
 
+    // If no scroll happened during a scroll gesture, it appears scrollbars and

[bokan, 2017/02/28 14:16:07]

nit: "appears" -> "fades in"

+    // schedules a fade out delay.
+    host_impl_->ScrollBegin(BeginState(gfx::Point()).get(),
+                            InputHandler::WHEEL);
+    host_impl_->ScrollBy(UpdateState(gfx::Point(), gfx::Vector2dF(0, 0)).get());
+    host_impl_->ScrollEnd(EndState().get());
+    EXPECT_FALSE(did_request_next_frame_);
+    EXPECT_FALSE(did_request_redraw_);
+    if (expecting_animations) {
+      EXPECT_EQ(base::TimeDelta::FromMilliseconds(20),
+                requested_animation_delay_);
+      EXPECT_FALSE(animation_task_.Equals(base::Closure()));
+      requested_animation_delay_ = base::TimeDelta();
+      animation_task_ = base::Closure();
+    } else {
+      EXPECT_EQ(base::TimeDelta(), requested_animation_delay_);
+      EXPECT_TRUE(animation_task_.Equals(base::Closure()));
+    }
+
     // Before the scrollbar animation exists, we should not get redraws.
     BeginFrameArgs begin_frame_args =
         CreateBeginFrameArgsForTesting(BEGINFRAME_FROM_HERE, 0, 2, fake_now);
     host_impl_->WillBeginImplFrame(begin_frame_args);
     host_impl_->Animate();
     EXPECT_FALSE(did_request_next_frame_);
     did_request_next_frame_ = false;
     EXPECT_FALSE(did_request_redraw_);
     did_request_redraw_ = false;
     EXPECT_EQ(base::TimeDelta(), requested_animation_delay_);
@@ skipping 100 matching lines @@
     host_impl_->ScrollBy(UpdateState(gfx::Point(), gfx::Vector2dF(5, 0)).get());
     EXPECT_FALSE(did_request_next_frame_);
     EXPECT_TRUE(did_request_redraw_);
     did_request_redraw_ = false;
     EXPECT_EQ(base::TimeDelta(), requested_animation_delay_);
     EXPECT_TRUE(animation_task_.Equals(base::Closure()));
 
     host_impl_->ScrollEnd(EndState().get());
     EXPECT_FALSE(did_request_next_frame_);
     EXPECT_FALSE(did_request_redraw_);
-    EXPECT_EQ(base::TimeDelta(), requested_animation_delay_);
-    EXPECT_TRUE(animation_task_.Equals(base::Closure()));
+
+    if (expecting_animations) {
+      EXPECT_EQ(base::TimeDelta::FromMilliseconds(20),
+                requested_animation_delay_);
+      EXPECT_FALSE(animation_task_.Equals(base::Closure()));
+      requested_animation_delay_ = base::TimeDelta();
+      animation_task_ = base::Closure();
+    } else {
+      EXPECT_EQ(base::TimeDelta(), requested_animation_delay_);
+      EXPECT_TRUE(animation_task_.Equals(base::Closure()));
+    }
 
     // Changing page scale triggers scrollbar animation.
     host_impl_->active_tree()->PushPageScaleFromMainThread(1.f, 1.f, 4.f);
     host_impl_->active_tree()->SetPageScaleOnActiveTree(1.1f);
     EXPECT_FALSE(did_request_next_frame_);
     EXPECT_FALSE(did_request_redraw_);
     if (expecting_animations) {
       EXPECT_EQ(base::TimeDelta::FromMilliseconds(20),
                 requested_animation_delay_);
       EXPECT_FALSE(animation_task_.Equals(base::Closure()));
@@ skipping 1014 matching lines @@
   host_impl_->ActivateSyncTree();
   // Scrolloffsets on the active tree will be clamped after activation.
   EXPECT_EQ(active_outer_layer->CurrentScrollOffset(), gfx::ScrollOffset(0, 0));
 }
 
 class LayerTreeHostImplBrowserControlsTest : public LayerTreeHostImplTest {
  public:
   LayerTreeHostImplBrowserControlsTest()
       // Make the clip size the same as the layer (content) size so the layer is
       // non-scrollable.
-      : layer_size_(10, 10),
-        clip_size_(layer_size_),
-        top_controls_height_(50) {
+      : layer_size_(10, 10), clip_size_(layer_size_), top_controls_height_(50) {
     viewport_size_ = gfx::Size(clip_size_.width(),
                                clip_size_.height() + top_controls_height_);
   }
 
   bool CreateHostImpl(
       const LayerTreeSettings& settings,
       std::unique_ptr<CompositorFrameSink> compositor_frame_sink) override {
     bool init = LayerTreeHostImplTest::CreateHostImpl(
         settings, std::move(compositor_frame_sink));
     if (init) {
@@ skipping 7916 matching lines @@
     else
       EXPECT_FALSE(tile->HasRasterTask());
   }
   Region expected_invalidation(
       raster_source->GetRectForImage(checkerable_image->uniqueID()));
   EXPECT_EQ(expected_invalidation, *(root->GetPendingInvalidation()));
 }
 
 }  // namespace
 }  // namespace cc