Fix Autohide -> None frame transition

This is reland of https://crrev.com/c/1164570

Change summary: A header view may outlive the target widget,
which can be differet widget. Reset the reference and check
before calling target widget.

Bug: b/112240082
Test: covered by unittests
Change-Id: Ia98d44a487b6cd2077b110e4a9799780cdbc4ebe
Reviewed-on: https://chromium-review.googlesource.com/1165697
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581350}

ash/frame/header_view.cc

@@ -241,7 +241,8 @@ void HeaderView::ChildPreferredSizeChanged(views::View* child) {
 void HeaderView::OnTabletModeStarted() {
   caption_button_container_->UpdateCaptionButtonState(true /*=animate*/);
   parent()->Layout();
-  if (Shell::Get()->tablet_mode_controller()->ShouldAutoHideTitlebars(
+  if (target_widget_ &&
+      Shell::Get()->tablet_mode_controller()->ShouldAutoHideTitlebars(
           target_widget_)) {
     target_widget_->non_client_view()->Layout();
   }
@@ -250,12 +251,16 @@ void HeaderView::OnTabletModeStarted() {
 void HeaderView::OnTabletModeEnded() {
   caption_button_container_->UpdateCaptionButtonState(true /*=animate*/);
   parent()->Layout();
-  target_widget_->non_client_view()->Layout();
+  if (target_widget_)
+    target_widget_->non_client_view()->Layout();
 }
 
 void HeaderView::OnWindowPropertyChanged(aura::Window* window,
                                          const void* key,
                                          intptr_t old) {
+  if (!target_widget_)
+    return;
+
   DCHECK_EQ(target_widget_->GetNativeWindow(), window);
   if (key == kFrameImageActiveKey || key == kFrameImageInactiveKey ||
       key == kFrameImageOverlayActiveKey ||
@@ -278,6 +283,8 @@ void HeaderView::OnWindowPropertyChanged(aura::Window* window,
 
 void HeaderView::OnWindowDestroying(aura::Window* window) {
   window_observer_.Remove(window);
+  // A HeaderView may outlive the target widget.
+  target_widget_ = nullptr;
 }
 
 views::View* HeaderView::avatar_icon() const {
@@ -349,7 +356,7 @@ std::vector<gfx::Rect> HeaderView::GetVisibleBoundsInScreen() const {
 }
 
 void HeaderView::PaintHeaderContent(gfx::Canvas* canvas) {
-  if (!should_paint_)
+  if (!should_paint_ || !target_widget_)
     return;
 
   bool paint_as_active =

components/exo/client_controlled_shell_surface.cc

@@ -907,8 +907,9 @@ gfx::Point ClientControlledShellSurface::GetSurfaceOrigin() const {
 // ClientControlledShellSurface, private:
 
 void ClientControlledShellSurface::UpdateFrame() {
-  if (!widget_ || !GetFrameView()->visible())
+  if (!widget_)
     return;
+
   gfx::Rect work_area =
       display::Screen::GetScreen()
           ->GetDisplayNearestWindow(widget_->GetNativeWindow())

components/exo/client_controlled_shell_surface_unittest.cc

@@ -555,6 +555,18 @@ TEST_F(ClientControlledShellSurfaceTest, Frame) {
   EXPECT_EQ(client_bounds, widget->GetWindowBoundsInScreen());
   EXPECT_EQ(client_bounds,
             frame_view->GetClientBoundsForWindowBounds(client_bounds));
+
+  // Test NONE -> AUTOHIDE -> NONE
+  shell_surface->SetMaximized();
+  shell_surface->SetGeometry(fullscreen_bounds);
+  surface->SetFrame(SurfaceFrameType::AUTOHIDE);
+  surface->Commit();
+  EXPECT_TRUE(frame_view->visible());
+  EXPECT_TRUE(frame_view->GetHeaderView()->in_immersive_mode());
+  surface->SetFrame(SurfaceFrameType::NONE);
+  surface->Commit();
+  EXPECT_FALSE(frame_view->visible());
+  EXPECT_FALSE(frame_view->GetHeaderView()->in_immersive_mode());
 }
 
 namespace {
@@ -1483,12 +1495,22 @@ TEST_F(ClientControlledShellSurfaceTest, WideFrame) {
   ASSERT_TRUE(wide_frame);
   EXPECT_FALSE(wide_frame->header_view()->in_immersive_mode());
 
-  // Set AutoHide mode.
+  // Test AUTOHIDE -> NORMAL
   surface->SetFrame(SurfaceFrameType::AUTOHIDE);
+  surface->Commit();
   EXPECT_TRUE(wide_frame->header_view()->in_immersive_mode());
 
-  // Exit AutoHide mode.
   surface->SetFrame(SurfaceFrameType::NORMAL);
+  surface->Commit();
+  EXPECT_FALSE(wide_frame->header_view()->in_immersive_mode());
+
+  // Test AUTOHIDE -> NONE
+  surface->SetFrame(SurfaceFrameType::AUTOHIDE);
+  surface->Commit();
+  EXPECT_TRUE(wide_frame->header_view()->in_immersive_mode());
+
+  surface->SetFrame(SurfaceFrameType::NONE);
+  surface->Commit();
   EXPECT_FALSE(wide_frame->header_view()->in_immersive_mode());
 
   // Unmaximize it and the frame should be normal.