Use MD-ash's auto hide behavior for arc++ windows.

ash/shelf/shelf_layout_manager.cc

Index: ash/shelf/shelf_layout_manager.cc
diff --git a/ash/shelf/shelf_layout_manager.cc b/ash/shelf/shelf_layout_manager.cc
index a4f758bb09fb8a1c7c388a4c82a533f309e85851..c83c0c8fd7d1a00f6c343c7268cabe5cd4ee28c9 100644
--- a/ash/shelf/shelf_layout_manager.cc
+++ b/ash/shelf/shelf_layout_manager.cc
@@ -239,6 +239,8 @@ void ShelfLayoutManager::UpdateVisibilityState() {
   if (!controller || !shelf_widget_->shelf() || in_shutdown_)
     return;
 
+  // Always reset to be safe.
+  invisible_auto_hide_shelf_ = false;
   if (state_.is_screen_locked || state_.is_adding_user_screen) {
     SetState(SHELF_VISIBLE);
   } else if (WmShell::Get()->IsPinned()) {
@@ -250,12 +252,29 @@ void ShelfLayoutManager::UpdateVisibilityState() {
         controller->GetWorkspaceWindowState());
     switch (window_state) {
       case wm::WORKSPACE_WINDOW_STATE_FULL_SCREEN: {
-        if (IsShelfHiddenForFullscreen()) {
-          SetState(SHELF_HIDDEN);
-        } else {
-          // The shelf is sometimes not hidden when in immersive fullscreen.
-          // Force the shelf to be auto hidden in this case.
-          SetState(SHELF_AUTO_HIDE);
+        switch (GetShelfModeForFullscreen()) {
+          case wm::WindowState::SHELF_HIDDEN:
+            SetState(SHELF_HIDDEN);
+            break;
+          case wm::WindowState::SHELF_AUTO_HIDE_VISIBLE:
+            // A hack to swtich the visibility state correctly
+            // between auto hide visible to auto hide invisible.
+            // TODO(oshima): Remove this once MD ash is launched.
+            if (state_.visibility_state == SHELF_AUTO_HIDE)
+              SetState(SHELF_HIDDEN);
+
+            SetState(SHELF_AUTO_HIDE);
+            break;
+          case wm::WindowState::SHELF_AUTO_HIDE_INVISIBLE:
+            // A hack to swtich the visibility state correctly
+            // between auto hide visible to auto hide invisible.
+            // TODO(oshima): Remove this once MD ash is launched.
+            if (state_.visibility_state == SHELF_AUTO_HIDE)
+              SetState(SHELF_HIDDEN);
+
+            invisible_auto_hide_shelf_ = true;
+            SetState(SHELF_AUTO_HIDE);
+            break;
         }
         break;
       }
@@ -795,7 +814,7 @@ void ShelfLayoutManager::UpdateTargetBoundsForGesture(
   } else {
     translate = gesture_drag_amount_;
   }
-  int shelf_insets = GetShelfConstant(SHELF_INSETS_FOR_AUTO_HIDE);
+  int shelf_insets = GetShelfInsetsForAutoHide();
   if (horizontal) {
     // Move and size the shelf with the gesture.
     int shelf_height = target_bounds->shelf_bounds_in_root.height() - translate;
@@ -988,7 +1007,7 @@ int ShelfLayoutManager::GetWorkAreaInsets(const State& state, int size) const {
   if (state.visibility_state == SHELF_VISIBLE)
     return size;
   if (state.visibility_state == SHELF_AUTO_HIDE)
-    return GetShelfConstant(SHELF_INSETS_FOR_AUTO_HIDE);
+    return GetShelfInsetsForAutoHide();
   return 0;
 }
 
@@ -1045,7 +1064,8 @@ float ShelfLayoutManager::ComputeTargetOpacity(const State& state) {
   // In Chrome OS Material Design, when shelf is hidden during auto hide state,
   // target bounds are also hidden. So the window can extend to the edge of
   // screen.
-  if (ash::MaterialDesignController::IsShelfMaterial()) {
+  if (ash::MaterialDesignController::IsShelfMaterial() ||
+      invisible_auto_hide_shelf_) {
     return (state.visibility_state == SHELF_AUTO_HIDE &&
             state.auto_hide_state == SHELF_AUTO_HIDE_SHOWN)
                ? 1.0f
@@ -1054,11 +1074,19 @@ float ShelfLayoutManager::ComputeTargetOpacity(const State& state) {
   return (state.visibility_state == SHELF_AUTO_HIDE) ? 1.0f : 0.0f;
 }
 
+ash::wm::WindowState::FullscreenShelfMode
+ShelfLayoutManager::GetShelfModeForFullscreen() const {
+  const WmWindow* fullscreen_window = wm::GetWindowForFullscreenMode(
+      WmLookup::Get()->GetWindowForWidget(shelf_widget_));
+  return fullscreen_window->GetWindowState()->shelf_mode_in_fullscreen();
+}
+
 bool ShelfLayoutManager::IsShelfHiddenForFullscreen() const {
   const WmWindow* fullscreen_window = wm::GetWindowForFullscreenMode(
       WmLookup::Get()->GetWindowForWidget(shelf_widget_));
   return fullscreen_window &&
-         fullscreen_window->GetWindowState()->hide_shelf_when_fullscreen();
+         fullscreen_window->GetWindowState()->shelf_mode_in_fullscreen() ==
+             ash::wm::WindowState::SHELF_HIDDEN;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -1156,4 +1184,10 @@ void ShelfLayoutManager::CancelGestureDrag() {
   gesture_drag_status_ = GESTURE_DRAG_NONE;
 }
 
+int ShelfLayoutManager::GetShelfInsetsForAutoHide() const {
+  if (invisible_auto_hide_shelf_)
+    return 0;
+  return GetShelfConstant(SHELF_INSETS_FOR_AUTO_HIDE);
+}
+
 }  // namespace ash