Honor overscroll-behavior CSS property in new gesture-nav UI

When overscroll-behavior-x for the root element of a page is set to
anything other than 'auto', gesture-nav should not start on the page.

Similarly, when overscroll-behavior-y for the root element of a page is
set to anything other than 'auto', pull-to-refresh should not start on
the page.

BUG=800074,742510
TEST=GestureNavSimpleTest.* in content_unittests

Change-Id: I86cf2f50c5ceb6613dc293c1fd32ca2cfff4daa2
Reviewed-on: https://chromium-review.googlesource.com/981127Reviewed-by: Sadrul Chowdhury <sadrul@chromium.org>
Commit-Queue: Mohsen Izadi <mohsen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#546736}

content/browser/web_contents/aura/gesture_nav_simple.cc

@@ -555,6 +555,12 @@ bool GestureNavSimple::OnOverscrollUpdate(float delta_x, float delta_y) {
 }
 
 void GestureNavSimple::OnOverscrollComplete(OverscrollMode overscroll_mode) {
+  if (mode_ == OverscrollMode::OVERSCROLL_NONE) {
+    // Previous mode change has been ignored because of overscroll-behavior
+    // value; so, ignore this, too.
+    return;
+  }
+
   DCHECK_EQ(mode_, overscroll_mode);
 
   mode_ = OVERSCROLL_NONE;
@@ -599,6 +605,29 @@ void GestureNavSimple::OnOverscrollModeChange(OverscrollMode old_mode,
                                               OverscrollMode new_mode,
                                               OverscrollSource source,
                                               cc::OverscrollBehavior behavior) {
+  DCHECK(old_mode == OverscrollMode::OVERSCROLL_NONE ||
+         new_mode == OverscrollMode::OVERSCROLL_NONE);
+
+  // Do not start a new gesture-nav if overscroll-behavior-x is not auto.
+  if ((new_mode == OverscrollMode::OVERSCROLL_EAST ||
+       new_mode == OverscrollMode::OVERSCROLL_WEST) &&
+      behavior.x != cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto) {
+    return;
+  }
+
+  // Do not start a new pull-to-refresh if overscroll-behavior-y is not auto.
+  if (new_mode == OverscrollMode::OVERSCROLL_SOUTH &&
+      behavior.y != cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto) {
+    return;
+  }
+
+  if (old_mode != OverscrollMode::OVERSCROLL_NONE &&
+      mode_ == OverscrollMode::OVERSCROLL_NONE) {
+    // Previous mode change has been ignored because of overscroll-behavior
+    // value; so, ignore this one, too.
+    return;
+  }
+
   DCHECK_EQ(mode_, old_mode);
   if (mode_ == new_mode)
     return;

content/browser/web_contents/aura/gesture_nav_simple.h

@@ -9,6 +9,7 @@
 
 #include "base/macros.h"
 #include "content/browser/renderer_host/overscroll_controller_delegate.h"
+#include "content/common/content_export.h"
 
 namespace content {
 
@@ -17,7 +18,7 @@ class WebContentsImpl;
 
 // A simple delegate for the overscroll controller that paints an arrow on top
 // of the web-contents as a hint for pending navigations from overscroll.
-class GestureNavSimple : public OverscrollControllerDelegate {
+class CONTENT_EXPORT GestureNavSimple : public OverscrollControllerDelegate {
  public:
   explicit GestureNavSimple(WebContentsImpl* web_contents);
   ~GestureNavSimple() override;
@@ -27,6 +28,8 @@ class GestureNavSimple : public OverscrollControllerDelegate {
   void OnAffordanceAnimationEnded();
 
  private:
+  friend class GestureNavSimpleTest;
+
   // OverscrollControllerDelegate:
   gfx::Size GetDisplaySize() const override;
   bool OnOverscrollUpdate(float delta_x, float delta_y) override;

content/browser/web_contents/aura/gesture_nav_simple_unittest.cc

+// Copyright 2018 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 "content/browser/web_contents/aura/gesture_nav_simple.h"
+
+#include "content/public/browser/browser_context.h"
+#include "content/public/browser/site_instance.h"
+#include "content/test/test_render_view_host.h"
+#include "content/test/test_web_contents.h"
+#include "ui/aura/window.h"
+
+#include <memory>
+
+namespace content {
+
+namespace {
+
+// A subclass of TestWebContents that offers a fake content window.
+class GestureNavTestWebContents : public TestWebContents {
+ public:
+  ~GestureNavTestWebContents() override {}
+
+  static GestureNavTestWebContents* Create(
+      BrowserContext* browser_context,
+      scoped_refptr<SiteInstance> instance,
+      std::unique_ptr<aura::Window> fake_native_view,
+      std::unique_ptr<aura::Window> fake_contents_window) {
+    auto* web_contents = new GestureNavTestWebContents(
+        browser_context, std::move(fake_native_view),
+        std::move(fake_contents_window));
+    web_contents->Init(
+        WebContents::CreateParams(browser_context, std::move(instance)));
+    return web_contents;
+  }
+
+  // Overriden from TestWebContents:
+  gfx::NativeView GetNativeView() override { return fake_native_view_.get(); }
+
+  gfx::NativeView GetContentNativeView() override {
+    return fake_contents_window_.get();
+  }
+
+ protected:
+  explicit GestureNavTestWebContents(
+      BrowserContext* browser_context,
+      std::unique_ptr<aura::Window> fake_native_view,
+      std::unique_ptr<aura::Window> fake_contents_window)
+      : TestWebContents(browser_context),
+        fake_native_view_(std::move(fake_native_view)),
+        fake_contents_window_(std::move(fake_contents_window)) {}
+
+ private:
+  std::unique_ptr<aura::Window> fake_native_view_;
+  std::unique_ptr<aura::Window> fake_contents_window_;
+};
+
+}  // namespace
+
+class GestureNavSimpleTest : public RenderViewHostImplTestHarness {
+ public:
+  GestureNavSimpleTest()
+      : first_("https://www.google.com"), second_("http://www.chromium.org") {}
+
+  ~GestureNavSimpleTest() override {}
+
+ protected:
+  // RenderViewHostImplTestHarness:
+  void SetUp() override {
+    RenderViewHostImplTestHarness::SetUp();
+
+    // Set up the fake web contents native view.
+    auto fake_native_view = std::make_unique<aura::Window>(nullptr);
+    fake_native_view->Init(ui::LAYER_SOLID_COLOR);
+    root_window()->AddChild(fake_native_view.get());
+    fake_native_view->SetBounds(gfx::Rect(root_window()->bounds().size()));
+
+    // Set up the fake contents window.
+    auto fake_contents_window = std::make_unique<aura::Window>(nullptr);
+    fake_contents_window->Init(ui::LAYER_SOLID_COLOR);
+    root_window()->AddChild(fake_contents_window.get());
+    fake_contents_window->SetBounds(gfx::Rect(root_window()->bounds().size()));
+
+    // Replace the default test web contents with our custom class.
+    SetContents(GestureNavTestWebContents::Create(
+        browser_context(), SiteInstance::Create(browser_context()),
+        std::move(fake_native_view), std::move(fake_contents_window)));
+
+    // Add two pages to navigation history.
+    contents()->NavigateAndCommit(first_);
+    EXPECT_TRUE(controller().GetVisibleEntry());
+    EXPECT_FALSE(controller().CanGoBack());
+
+    contents()->NavigateAndCommit(second_);
+    EXPECT_TRUE(controller().CanGoBack());
+    EXPECT_FALSE(controller().CanGoForward());
+
+    gesture_nav_simple_ = std::make_unique<GestureNavSimple>(contents());
+  }
+
+  void TearDown() override {
+    gesture_nav_simple_ = nullptr;
+    RenderViewHostImplTestHarness::TearDown();
+  }
+
+  const GURL first() const { return first_; }
+  const GURL second() const { return second_; }
+
+  void OnOverscrollModeChange(OverscrollMode old_mode,
+                              OverscrollMode new_mode,
+                              OverscrollSource source,
+                              cc::OverscrollBehavior behavior) {
+    gesture_nav_simple_->OnOverscrollModeChange(old_mode, new_mode, source,
+                                                behavior);
+  }
+
+  void OnOverscrollComplete(OverscrollMode overscroll_mode) {
+    gesture_nav_simple_->OnOverscrollComplete(overscroll_mode);
+  }
+
+  OverscrollMode mode() const { return gesture_nav_simple_->mode_; }
+  OverscrollSource source() const { return gesture_nav_simple_->source_; }
+
+ private:
+  // Test URLs.
+  const GURL first_;
+  const GURL second_;
+
+  std::unique_ptr<GestureNavSimple> gesture_nav_simple_;
+
+  DISALLOW_COPY_AND_ASSIGN(GestureNavSimpleTest);
+};
+
+// Tests that setting 'overscroll-behavior-x' to 'auto' allows gesture-nav.
+TEST_F(GestureNavSimpleTest, OverscrollBehaviorXAutoAllowsGestureNav) {
+  EXPECT_EQ(second(), contents()->GetURL());
+
+  cc::OverscrollBehavior behavior_x_auto;
+  behavior_x_auto.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_auto);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_EAST, mode());
+  EXPECT_EQ(OverscrollSource::TOUCHSCREEN, source());
+}
+
+// Tests that setting 'overscroll-behavior-x' to 'contain' prevents gesture-nav.
+TEST_F(GestureNavSimpleTest, OverscrollBehaviorXContainPreventsGestureNav) {
+  EXPECT_EQ(second(), contents()->GetURL());
+
+  cc::OverscrollBehavior behavior_x_contain;
+  behavior_x_contain.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+// Tests that setting 'overscroll-behavior-x' to 'none' prevents gesture-nav.
+TEST_F(GestureNavSimpleTest, OverscrollBehaviorXNonePreventsGestureNav) {
+  EXPECT_EQ(second(), contents()->GetURL());
+
+  cc::OverscrollBehavior behavior_x_none;
+  behavior_x_none.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeNone;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_none);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+// Tests that setting 'overscroll-behavior-y' to 'auto' allows pull-to-refresh.
+TEST_F(GestureNavSimpleTest, OverscrollBehaviorYAutoAllowsPullToRefresh) {
+  cc::OverscrollBehavior behavior_y_auto;
+  behavior_y_auto.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_auto);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_SOUTH, mode());
+  EXPECT_EQ(OverscrollSource::TOUCHSCREEN, source());
+}
+
+// Tests that setting 'overscroll-behavior-y' to 'contain' prevents
+// pull-to-refresh.
+TEST_F(GestureNavSimpleTest, OverscrollBehaviorYContainPreventsPullToRefresh) {
+  cc::OverscrollBehavior behavior_y_contain;
+  behavior_y_contain.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+// Tests that setting 'overscroll-behavior-y' to 'none' prevents
+// pull-to-refresh.
+TEST_F(GestureNavSimpleTest, OverscrollBehaviorYNonePreventsPullToRefresh) {
+  cc::OverscrollBehavior behavior_y_none;
+  behavior_y_none.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeNone;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_none);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+// Tests that setting 'overscroll-behavior-x' to a value that prevents
+// gesture-nav after it has started does not affect aborting it.
+TEST_F(GestureNavSimpleTest, PreventGestureNavBeforeAbort) {
+  EXPECT_EQ(second(), contents()->GetURL());
+
+  cc::OverscrollBehavior behavior_x_auto;
+  behavior_x_auto.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto;
+  cc::OverscrollBehavior behavior_x_contain;
+  behavior_x_contain.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_auto);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_EAST, mode());
+  EXPECT_EQ(OverscrollSource::TOUCHSCREEN, source());
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+  EXPECT_EQ(second(), contents()->GetURL());
+}
+
+// Tests that after gesture-nav was prevented due to 'overscroll-behavior-x',
+// setting it to 'auto' does not affect aborting overscroll.
+TEST_F(GestureNavSimpleTest, AllowGestureNavBeforeAbort) {
+  EXPECT_EQ(second(), contents()->GetURL());
+
+  cc::OverscrollBehavior behavior_x_contain;
+  behavior_x_contain.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+  cc::OverscrollBehavior behavior_x_auto;
+  behavior_x_auto.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_auto);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+  EXPECT_EQ(second(), contents()->GetURL());
+}
+
+// Tests that preventing gesture-nav using 'overscroll-behavior-x' does not
+// affect completing overscroll.
+TEST_F(GestureNavSimpleTest, CompletePreventedGestureNav) {
+  EXPECT_EQ(second(), contents()->GetURL());
+
+  cc::OverscrollBehavior behavior_x_contain;
+  behavior_x_contain.x = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_EAST,
+                         OverscrollSource::TOUCHSCREEN, behavior_x_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+
+  OnOverscrollComplete(OverscrollMode::OVERSCROLL_EAST);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+  EXPECT_EQ(second(), contents()->GetURL());
+}
+
+// Tests that setting 'overscroll-behavior-y' to a value that prevents
+// pull-to-refresh after it has started does not affect aborting it.
+TEST_F(GestureNavSimpleTest, PreventPullToRefreshBeforeAbort) {
+  cc::OverscrollBehavior behavior_y_auto;
+  behavior_y_auto.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto;
+  cc::OverscrollBehavior behavior_y_contain;
+  behavior_y_contain.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_auto);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_SOUTH, mode());
+  EXPECT_EQ(OverscrollSource::TOUCHSCREEN, source());
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+// Tests that after pull-to-refresh was prevented due to
+// 'overscroll-behavior-y', setting it to 'auto' does not affect aborting
+// overscroll.
+TEST_F(GestureNavSimpleTest, AllowPullToRefreshBeforeAbort) {
+  cc::OverscrollBehavior behavior_y_contain;
+  behavior_y_contain.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+  cc::OverscrollBehavior behavior_y_auto;
+  behavior_y_auto.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeAuto;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_auto);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+// Tests that preventing pull-to-refresh using 'overscroll-behavior-y' does not
+// affect completing overscroll.
+TEST_F(GestureNavSimpleTest, CompletePreventedPullToRefresh) {
+  cc::OverscrollBehavior behavior_y_contain;
+  behavior_y_contain.y = cc::OverscrollBehavior::kOverscrollBehaviorTypeContain;
+
+  OnOverscrollModeChange(OverscrollMode::OVERSCROLL_NONE,
+                         OverscrollMode::OVERSCROLL_SOUTH,
+                         OverscrollSource::TOUCHSCREEN, behavior_y_contain);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+
+  OnOverscrollComplete(OverscrollMode::OVERSCROLL_SOUTH);
+
+  EXPECT_EQ(OverscrollMode::OVERSCROLL_NONE, mode());
+  EXPECT_EQ(OverscrollSource::NONE, source());
+}
+
+}  // namespace content

content/test/BUILD.gn

@@ -1497,6 +1497,7 @@ test("content_unittests") {
     "../browser/tracing/background_memory_tracing_observer_unittest.cc",
     "../browser/tracing/background_tracing_config_unittest.cc",
     "../browser/tracing/tracing_ui_unittest.cc",
+    "../browser/web_contents/aura/gesture_nav_simple_unittest.cc",
     "../browser/web_contents/aura/overscroll_navigation_overlay_unittest.cc",
     "../browser/web_contents/aura/overscroll_window_animation_unittest.cc",
     "../browser/web_contents/aura/overscroll_window_delegate_unittest.cc",
@@ -2025,6 +2026,7 @@ test("content_unittests") {
   } else {
     sources -= [
       "../browser/renderer_host/render_widget_host_view_aura_unittest.cc",
+      "../browser/web_contents/aura/gesture_nav_simple_unittest.cc",
       "../browser/web_contents/aura/overscroll_navigation_overlay_unittest.cc",
       "../browser/web_contents/aura/overscroll_window_animation_unittest.cc",
       "../browser/web_contents/aura/overscroll_window_delegate_unittest.cc",