Fix chromevox state transition announcement

- When ChromeVox is enabled, launcher state transitions to peeking or
  fullscreen are now announced.
- This fix also removes the ability to focus on the expand arrow while
  in fullscreen.

Bug: 779687
Change-Id: I942737bed53c258272aaea1a379cb7dd4053f605
Reviewed-on: https://chromium-review.googlesource.com/c/1423741Reviewed-by: Dominic Mazzoni <dmazzoni@chromium.org>
Reviewed-by: David Tseng <dtseng@chromium.org>
Reviewed-by: Weidong Guo <weidongg@chromium.org>
Commit-Queue: Matthew Mourgos <mmourgos@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625756}

ash/app_list/views/app_list_view.cc

@@ -45,6 +45,7 @@
 #include "ui/gfx/skia_util.h"
 #include "ui/keyboard/keyboard_controller.h"
 #include "ui/strings/grit/ui_strings.h"
+#include "ui/views/accessibility/view_accessibility.h"
 #include "ui/views/controls/image_view.h"
 #include "ui/views/controls/textfield/textfield.h"
 #include "ui/views/layout/fill_layout.h"
@@ -478,11 +479,6 @@ void AppListView::Layout() {
   UpdateAppListBackgroundYPosition();
 }
 
-void AppListView::GetAccessibleNodeData(ui::AXNodeData* node_data) {
-  node_data->SetName(state_announcement_);
-  node_data->role = ax::mojom::Role::kAlert;
-}
-
 ax::mojom::Role AppListView::GetAccessibleWindowRole() const {
   // Default role of root view is ax::mojom::Role::kWindow which traps ChromeVox
   // focus within the root view. Assign ax::mojom::Role::kGroup here to allow
@@ -549,6 +545,9 @@ void AppListView::InitContents(int initial_apps_page) {
   search_box_view_->Init();
 
   app_list_main_view_->Init(0, search_box_view_);
+
+  announcement_view_ = new views::View;
+  AddChildView(announcement_view_);
 }
 
 void AppListView::InitChildWidgets() {
@@ -887,17 +886,17 @@ void AppListView::MaybeCreateAccessibilityEvent(AppListViewState new_state) {
       new_state != AppListViewState::FULLSCREEN_ALL_APPS)
     return;
 
-  DCHECK(state_announcement_ == base::string16());
+  base::string16 state_announcement;
 
   if (new_state == AppListViewState::PEEKING) {
-    state_announcement_ = l10n_util::GetStringUTF16(
+    state_announcement = l10n_util::GetStringUTF16(
         IDS_APP_LIST_SUGGESTED_APPS_ACCESSIBILITY_ANNOUNCEMENT);
   } else {
-    state_announcement_ = l10n_util::GetStringUTF16(
+    state_announcement = l10n_util::GetStringUTF16(
         IDS_APP_LIST_ALL_APPS_ACCESSIBILITY_ANNOUNCEMENT);
   }
-  NotifyAccessibilityEvent(ax::mojom::Event::kAlert, true);
-  state_announcement_ = base::string16();
+  announcement_view_->GetViewAccessibility().OverrideName(state_announcement);
+  announcement_view_->NotifyAccessibilityEvent(ax::mojom::Event::kAlert, true);
 }
 
 display::Display AppListView::GetDisplayNearestView() const {

ash/app_list/views/app_list_view.h

@@ -131,7 +131,6 @@ class APP_LIST_EXPORT AppListView : public views::WidgetDelegateView {
   bool CanProcessEventsWithinSubtree() const override;
   bool AcceleratorPressed(const ui::Accelerator& accelerator) override;
   void Layout() override;
-  void GetAccessibleNodeData(ui::AXNodeData* node_data) override;
 
   // WidgetDelegate:
   ax::mojom::Role GetAccessibleWindowRole() const override;
@@ -404,9 +403,6 @@ class APP_LIST_EXPORT AppListView : public views::WidgetDelegateView {
   // True if the dragging started from PEEKING state.
   bool drag_started_from_peeking_ = false;
 
-  // Accessibility announcement dialogue.
-  base::string16 state_announcement_;
-
   // Metric reporter for state change animations.
   const std::unique_ptr<ui::AnimationMetricsReporter>
       state_animation_metrics_reporter_;
@@ -414,6 +410,9 @@ class APP_LIST_EXPORT AppListView : public views::WidgetDelegateView {
   // Whether the on-screen keyboard is shown.
   bool onscreen_keyboard_shown_ = false;
 
+  // View used to announce the state transition for peeking and fullscreen.
+  views::View* announcement_view_;  // Owned by AppListView.
+
   base::WeakPtrFactory<AppListView> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AppListView);

ash/app_list/views/contents_view.cc

@@ -30,6 +30,7 @@
 #include "ui/display/screen.h"
 #include "ui/events/event.h"
 #include "ui/keyboard/keyboard_controller.h"
+#include "ui/views/accessibility/view_accessibility.h"
 #include "ui/views/view_model.h"
 #include "ui/views/widget/widget.h"
 
@@ -353,15 +354,21 @@ void ContentsView::UpdateExpandArrowOpacity(double progress,
 
 void ContentsView::UpdateExpandArrowFocusBehavior(
     ash::AppListState current_state) {
-  if (current_state == ash::AppListState::kStateStart) {
-    // The expand arrow is only focusable and has InkDropMode on in peeking
-    // state.
-    expand_arrow_view_->SetFocusBehavior(FocusBehavior::ALWAYS);
-    expand_arrow_view_->SetInkDropMode(views::InkDropHostView::InkDropMode::ON);
-    return;
-  }
-  expand_arrow_view_->SetInkDropMode(views::InkDropHostView::InkDropMode::OFF);
-  expand_arrow_view_->SetFocusBehavior(FocusBehavior::NEVER);
+  bool state_start = current_state == ash::AppListState::kStateStart;
+
+  // The expand arrow is only focusable and has InkDropMode on in peeking
+  // state.
+  expand_arrow_view_->SetFocusBehavior(state_start ? FocusBehavior::ALWAYS
+                                                   : FocusBehavior::NEVER);
+  expand_arrow_view_->SetInkDropMode(
+      state_start ? views::InkDropHostView::InkDropMode::ON
+                  : views::InkDropHostView::InkDropMode::OFF);
+
+  // Allow ChromeVox to focus the expand arrow only when peeking launcher.
+  expand_arrow_view_->GetViewAccessibility().OverrideIsIgnored(
+      state_start ? false : true);
+  expand_arrow_view_->GetViewAccessibility().NotifyAccessibilityEvent(
+      ax::mojom::Event::kTreeChanged);
 }
 
 PaginationModel* ContentsView::GetAppsPaginationModel() {

chrome/browser/chromeos/accessibility/spoken_feedback_browsertest.cc

@@ -350,6 +350,81 @@ IN_PROC_BROWSER_TEST_P(SpokenFeedbackTest, DISABLED_TypeInOmnibox) {
   EXPECT_EQ("z", speech_monitor_.GetNextUtterance());
 }
 
+IN_PROC_BROWSER_TEST_P(SpokenFeedbackTest, LauncherStateTransition) {
+  EnableChromeVox();
+
+  EXPECT_TRUE(PerformAcceleratorAction(ash::FOCUS_SHELF));
+
+  while (true) {
+    std::string utterance = speech_monitor_.GetNextUtterance();
+    if (base::MatchPattern(utterance, "Launcher"))
+      break;
+  }
+
+  EXPECT_EQ("Button", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ("Shelf", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ("Tool bar", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ(", window", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ("Press Search plus Space to activate.",
+            speech_monitor_.GetNextUtterance());
+
+  // Press space on the launcher button in shelf, this opens peeking launcher.
+  SendKeyPressWithSearch(ui::VKEY_SPACE);
+  EXPECT_EQ("Edit text", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ(", window", speech_monitor_.GetNextUtterance());
+
+  // Check that Launcher, partial view state is announced.
+  EXPECT_EQ("Launcher, partial view", speech_monitor_.GetNextUtterance());
+
+  // Move focus to expand all apps button;
+  SendKeyPressWithSearchAndShift(ui::VKEY_TAB);
+  EXPECT_EQ("Expand to all apps", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ("Button", speech_monitor_.GetNextUtterance());
+  EXPECT_EQ("Press Search plus Space to activate.",
+            speech_monitor_.GetNextUtterance());
+
+  // Press space on expand arrow to go to fullscreen launcher.
+  SendKeyPressWithSearch(ui::VKEY_SPACE);
+  EXPECT_EQ("Edit text", speech_monitor_.GetNextUtterance());
+
+  // Check that Launcher, all apps state is announced.
+  EXPECT_EQ("Launcher, all apps", speech_monitor_.GetNextUtterance());
+}
+
+IN_PROC_BROWSER_TEST_P(SpokenFeedbackTest, DisabledFullscreenExpandButton) {
+  EnableChromeVox();
+
+  EXPECT_TRUE(PerformAcceleratorAction(ash::FOCUS_SHELF));
+
+  while (speech_monitor_.GetNextUtterance() !=
+         "Press Search plus Space to activate.") {
+  }
+
+  // Press space on the launcher button in shelf, this opens peeking launcher.
+  SendKeyPressWithSearch(ui::VKEY_SPACE);
+  while (speech_monitor_.GetNextUtterance() != "Launcher, partial view") {
+  }
+
+  // Move focus to expand all apps button.
+  SendKeyPressWithSearchAndShift(ui::VKEY_TAB);
+  while (speech_monitor_.GetNextUtterance() !=
+         "Press Search plus Space to activate.") {
+  }
+
+  // Press space on expand arrow to go to fullscreen launcher.
+  SendKeyPressWithSearch(ui::VKEY_SPACE);
+  while (speech_monitor_.GetNextUtterance() != "Launcher, all apps") {
+  }
+
+  // Make sure the first traversal left is not the expand arrow button.
+  SendKeyPressWithSearch(ui::VKEY_LEFT);
+  EXPECT_NE("Expand to all apps", speech_monitor_.GetNextUtterance());
+
+  // Make sure the second traversal left is not the expand arrow button.
+  SendKeyPressWithSearch(ui::VKEY_LEFT);
+  EXPECT_NE("Expand to all apps", speech_monitor_.GetNextUtterance());
+}
+
 IN_PROC_BROWSER_TEST_P(SpokenFeedbackTest, FocusShelf) {
   EnableChromeVox();