Do not change the workspace when entering/leaving overview

* This also fixes the IsSelecting so that it returns false
during shutdown.

BUG=834400
TEST=Covered by unit test

Change-Id: Iac0cb8a3bdf03609727c31c51000c52ececfc66a
Reviewed-on: https://chromium-review.googlesource.com/1140749
Commit-Queue: Mitsuru Oshima <oshima@chromium.org>
Reviewed-by: Sammie Quon <sammiequon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#576078}

ash/shelf/shelf_layout_manager.cc

@@ -28,6 +28,7 @@
 #include "ash/system/status_area_widget.h"
 #include "ash/wm/fullscreen_window_finder.h"
 #include "ash/wm/mru_window_tracker.h"
+#include "ash/wm/overview/window_selector_controller.h"
 #include "ash/wm/screen_pinning_controller.h"
 #include "ash/wm/tablet_mode/tablet_mode_controller.h"
 #include "ash/wm/window_state.h"
@@ -673,7 +674,9 @@ void ShelfLayoutManager::UpdateBoundsAndOpacity(
     const display::Display display =
         display::Screen::GetScreen()->GetDisplayNearestWindow(
             shelf_widget_->GetNativeWindow());
-    if (!state_.IsScreenLocked() && change_work_area &&
+    bool in_overview =
+        Shell::Get()->window_selector_controller()->IsSelecting();
+    if (!in_overview && !state_.IsScreenLocked() && change_work_area &&
         (shelf_->alignment() != SHELF_ALIGNMENT_BOTTOM_LOCKED ||
          display.work_area() == display.bounds())) {
       gfx::Insets insets;

ash/wm/overview/window_selector_controller.cc

@@ -410,10 +410,10 @@ void WindowSelectorController::OnSelectionEnded() {
     overview_blur_controller_->Unblur();
   is_shutting_down_ = true;
   Shell::Get()->NotifyOverviewModeEnding();
-  window_selector_->Shutdown();
+  auto* window_selector = window_selector_.release();
+  window_selector->Shutdown();
   // Don't delete |window_selector_| yet since the stack is still using it.
-  base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE,
-                                                  window_selector_.release());
+  base::ThreadTaskRunnerHandle::Get()->DeleteSoon(FROM_HERE, window_selector);
   last_selection_time_ = base::Time::Now();
   Shell::Get()->NotifyOverviewModeEnded();
   is_shutting_down_ = false;

ash/wm/overview/window_selector_unittest.cc

@@ -949,6 +949,7 @@ TEST_F(WindowSelectorTest, SkipOverviewWindow) {
 // mode correctly applies the transformations to the window and correctly
 // updates the window bounds on exiting overview mode: http://crbug.com/401664.
 TEST_F(WindowSelectorTest, FullscreenWindowTabletMode) {
+  UpdateDisplay("800x600");
   const gfx::Rect bounds(400, 400);
   std::unique_ptr<aura::Window> window1(CreateWindow(bounds));
   std::unique_ptr<aura::Window> window2(CreateWindow(bounds));
@@ -961,13 +962,24 @@ TEST_F(WindowSelectorTest, FullscreenWindowTabletMode) {
   gfx::Rect fullscreen_window_bounds(window1->bounds());
   EXPECT_NE(normal_window_bounds, fullscreen_window_bounds);
   EXPECT_EQ(fullscreen_window_bounds, window2->GetTargetBounds());
+
+  const gfx::Rect fullscreen(800, 600);
+  const gfx::Rect normal_work_area(800, 552);
+  display::Screen* screen = display::Screen::GetScreen();
+  EXPECT_EQ(gfx::Rect(800, 600),
+            screen->GetDisplayNearestWindow(window1.get()).work_area());
+
   ToggleOverview();
+  EXPECT_EQ(fullscreen,
+            screen->GetDisplayNearestWindow(window1.get()).work_area());
+
   // Window 2 would normally resize to normal window bounds on showing the shelf
   // for overview but this is deferred until overview is exited.
   EXPECT_EQ(fullscreen_window_bounds, window2->GetTargetBounds());
   EXPECT_FALSE(WindowsOverlapping(window1.get(), window2.get()));
   ToggleOverview();
-
+  EXPECT_EQ(fullscreen,
+            screen->GetDisplayNearestWindow(window1.get()).work_area());
   // Since the fullscreen window is still active, window2 will still have the
   // larger bounds.
   EXPECT_EQ(fullscreen_window_bounds, window2->GetTargetBounds());
@@ -976,7 +988,19 @@ TEST_F(WindowSelectorTest, FullscreenWindowTabletMode) {
   // the shelf bringing window2 back to the normal bounds.
   ToggleOverview();
   ClickWindow(window2.get());
+  // Selecting non fullscreen window should set the work area back to normal.
+  EXPECT_EQ(normal_work_area,
+            screen->GetDisplayNearestWindow(window1.get()).work_area());
   EXPECT_EQ(normal_window_bounds, window2->GetTargetBounds());
+
+  ToggleOverview();
+  EXPECT_EQ(normal_work_area,
+            screen->GetDisplayNearestWindow(window1.get()).work_area());
+  ClickWindow(window1.get());
+  // Selecting fullscreen. The work area should be updated to fullscreen as
+  // well.
+  EXPECT_EQ(fullscreen,
+            screen->GetDisplayNearestWindow(window1.get()).work_area());
 }
 
 // Tests that beginning window selection hides the app list.