Revert of Support Compat mode inside of the desktop tree. (patchset #12 id:220001 of https://codereview.chromium.org/1191783002/)

Reason for revert:
Parent change reverted.
https://codereview.chromium.org/1185753008/

Original issue's description:
> Support Compat mode inside of the desktop tree.
>
> Depends on
> https://codereview.chromium.org/1185753008/
>
> Removes native bindings for Search+Shift+Arrows in favor of the extension commands bindings. Enables all ChromeVox Compat/Next commands inside of the desktop tree. Adds a test to exercise next element and next button commands.
>
> Also, whitelists root nodes without urls for ChromeVox compat. This includes the shelf/launcher.
>
> TEST=SpokenFeedbackTest.*
>
> Committed: https://crrev.com/e7b1c72c03dcf636e50917b2c8122e5d0ef884b6
> Cr-Commit-Position: refs/heads/master@{#336181}

TBR=dmazzoni@chromium.org,oshima@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review URL: https://codereview.chromium.org/1213513003

Cr-Commit-Position: refs/heads/master@{#336195}

3 files changed, 49 insertions, 0 deletions

diff --git a/ash/accelerators/accelerator_controller.cc b/ash/accelerators/accelerator_controller.cc
index 8f1d947..6eb68a3 100644
--- a/ash/accelerators/accelerator_controller.cc
+++ b/ash/accelerators/accelerator_controller.cc
@@ -79,6 +79,37 @@ namespace {
 
 using base::UserMetricsAction;
 
+bool CanHandleAccessibleFocusCycle() {
+  if (!Shell::GetInstance()->accessibility_delegate()->
+      IsSpokenFeedbackEnabled()) {
+    return false;
+  }
+  aura::Window* active_window = ash::wm::GetActiveWindow();
+  if (!active_window)
+    return false;
+  views::Widget* widget =
+      views::Widget::GetWidgetForNativeWindow(active_window);
+  if (!widget)
+    return false;
+  views::FocusManager* focus_manager = widget->GetFocusManager();
+  if (!focus_manager)
+    return false;
+  views::View* view = focus_manager->GetFocusedView();
+  return view && strcmp(view->GetClassName(), views::WebView::kViewClassName);
+}
+
+void HandleAccessibleFocusCycle(bool reverse) {
+  if (reverse)
+    base::RecordAction(UserMetricsAction("Accel_Accessible_Focus_Previous"));
+  else
+    base::RecordAction(UserMetricsAction("Accel_Accessible_Focus_Next"));
+
+  aura::Window* active_window = ash::wm::GetActiveWindow();
+  views::Widget* widget =
+      views::Widget::GetWidgetForNativeWindow(active_window);
+  widget->GetFocusManager()->AdvanceFocus(reverse);
+}
+
 void HandleCycleBackwardMRU(const ui::Accelerator& accelerator) {
   if (accelerator.key_code() == ui::VKEY_TAB)
     base::RecordAction(base::UserMetricsAction("Accel_PrevWindow_Tab"));
@@ -849,6 +880,9 @@ bool AcceleratorController::CanPerformAction(
   // false should be returned to give the web contents a chance at handling the
   // accelerator.
   switch (action) {
+    case ACCESSIBLE_FOCUS_NEXT:
+    case ACCESSIBLE_FOCUS_PREVIOUS:
+      return CanHandleAccessibleFocusCycle();
     case DEBUG_PRINT_LAYER_HIERARCHY:
     case DEBUG_PRINT_VIEW_HIERARCHY:
     case DEBUG_PRINT_WINDOW_HIERARCHY:
@@ -979,6 +1013,12 @@ void AcceleratorController::PerformAction(AcceleratorAction action,
   // implement it in your module's controller code (like TOGGLE_MIRROR_MODE
   // below) or pull it into a HandleFoo() function above.
   switch (action) {
+    case ACCESSIBLE_FOCUS_NEXT:
+      HandleAccessibleFocusCycle(false);
+      break;
+    case ACCESSIBLE_FOCUS_PREVIOUS:
+      HandleAccessibleFocusCycle(true);
+      break;
     case CYCLE_BACKWARD_MRU:
       HandleCycleBackwardMRU(accelerator);
       break;
diff --git a/ash/accelerators/accelerator_table.cc b/ash/accelerators/accelerator_table.cc
index 446819c..93ddb01 100644
--- a/ash/accelerators/accelerator_table.cc
+++ b/ash/accelerators/accelerator_table.cc
@@ -171,6 +171,11 @@ const AcceleratorData kAcceleratorData[] = {
   { true, ui::VKEY_U, ui::EF_CONTROL_DOWN | ui::EF_ALT_DOWN | ui::EF_SHIFT_DOWN,
     PRINT_UI_HIERARCHIES },
 
+  { false, ui::VKEY_HOME, ui::EF_SHIFT_DOWN, ACCESSIBLE_FOCUS_PREVIOUS},
+  { false, ui::VKEY_PRIOR, ui::EF_SHIFT_DOWN, ACCESSIBLE_FOCUS_PREVIOUS},
+  { false, ui::VKEY_END, ui::EF_SHIFT_DOWN, ACCESSIBLE_FOCUS_NEXT},
+  { false, ui::VKEY_NEXT, ui::EF_SHIFT_DOWN, ACCESSIBLE_FOCUS_NEXT},
+
   // TODO(yusukes): Handle VKEY_MEDIA_STOP, and
   // VKEY_MEDIA_LAUNCH_MAIL.
 };
@@ -403,6 +408,8 @@ const size_t kActionsAllowedInAppModeLength =
     arraysize(kActionsAllowedInAppMode);
 
 const AcceleratorAction kActionsNeedingWindow[] = {
+    ACCESSIBLE_FOCUS_NEXT,
+    ACCESSIBLE_FOCUS_PREVIOUS,
     CYCLE_BACKWARD_MRU,
     CYCLE_FORWARD_MRU,
     TOGGLE_OVERVIEW,
diff --git a/ash/accelerators/accelerator_table.h b/ash/accelerators/accelerator_table.h
index 86ec318..1d478a0 100644
--- a/ash/accelerators/accelerator_table.h
+++ b/ash/accelerators/accelerator_table.h
@@ -51,6 +51,8 @@ namespace ash {
 // Please put if/def sections at the end of the bare section and keep the list
 // within each section in alphabetical order.
 enum AcceleratorAction {
+  ACCESSIBLE_FOCUS_NEXT,
+  ACCESSIBLE_FOCUS_PREVIOUS,
   CYCLE_BACKWARD_MRU,
   CYCLE_FORWARD_MRU,
   DEBUG_PRINT_LAYER_HIERARCHY,