Activate an unsnappable window should end both splitview and overview.

Bug: 880959
Change-Id: I87d4d222ea3b748171624846bfade66cca994a1b
Reviewed-on: https://chromium-review.googlesource.com/1208145Reviewed-by: Xiyuan Xia <xiyuan@chromium.org>
Commit-Queue: Xiaoqian Dai <xdai@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589181}

ash/wm/overview/window_selector.cc

@@ -929,14 +929,21 @@ bool WindowSelector::HandleKeyEvent(views::Textfield* sender,
 void WindowSelector::OnSplitViewStateChanged(
     SplitViewController::State previous_state,
     SplitViewController::State state) {
-  if (state != SplitViewController::NO_SNAP) {
-    // Do not restore focus if a window was just snapped and activated.
+  const bool unsnappable_window_activated =
+      state == SplitViewController::NO_SNAP &&
+      Shell::Get()->split_view_controller()->end_reason() ==
+          SplitViewController::EndReason::kUnsnappableWindowActivated;
+
+  if (state != SplitViewController::NO_SNAP || unsnappable_window_activated) {
+    // Do not restore focus if a window was just snapped and activated or
+    // splitview mode is ended by activating an unsnappable window.
     ResetFocusRestoreWindow(false);
   }
 
-  if (state == SplitViewController::BOTH_SNAPPED) {
-    // If two windows were snapped to both sides of the screen, end overview
-    // mode.
+  if (state == SplitViewController::BOTH_SNAPPED ||
+      unsnappable_window_activated) {
+    // If two windows were snapped to both sides of the screen or an unsnappable
+    // window was just activated, end overview mode.
     CancelSelection();
   } else {
     // Otherwise adjust the overview window grid bounds if overview mode is

ash/wm/splitview/split_view_controller.cc

@@ -695,7 +695,7 @@ void SplitViewController::OnWindowActivated(ActivationReason reason,
   // mode and show the cannot snap toast.
   if (!CanSnap(gained_active)) {
     if (wm::GetWindowState(gained_active)->IsUserPositionable()) {
-      EndSplitView();
+      EndSplitView(EndReason::kUnsnappableWindowActivated);
       ShowAppCannotSnapToast();
     }
     return;

ash/wm/splitview/split_view_controller.h

@@ -58,10 +58,12 @@ class ASH_EXPORT SplitViewController : public mojom::SplitViewController,
   enum SnapPosition { NONE, LEFT, RIGHT };
 
   // Why splitview was ended. For now, all reasons will be kNormal except when
-  // the home launcher button is pressed.
+  // the home launcher button is pressed or an unsnappable window just got
+  // activated.
   enum class EndReason {
     kNormal = 0,
     kHomeLauncherPressed,
+    kUnsnappableWindowActivated,
   };
 
   class Observer {

ash/wm/splitview/split_view_controller_unittest.cc

@@ -1596,6 +1596,24 @@ TEST_F(SplitViewControllerTest, WindowStateOnExit) {
   EXPECT_FALSE(wm::GetWindowState(window2.get())->IsMaximized());
 }
 
+// Test that if overview and splitview are both active at the same time,
+// activiate an unsnappable window should end both overview and splitview mode.
+TEST_F(SplitViewControllerTest, ActivateNonSnappableWindow) {
+  const gfx::Rect bounds(0, 0, 400, 400);
+  std::unique_ptr<aura::Window> window1(CreateWindow(bounds));
+  std::unique_ptr<aura::Window> window2(CreateWindow(bounds));
+  std::unique_ptr<aura::Window> window3(CreateNonSnappableWindow(bounds));
+
+  split_view_controller()->SnapWindow(window1.get(), SplitViewController::LEFT);
+  ToggleOverview();
+  EXPECT_TRUE(split_view_controller()->IsSplitViewModeActive());
+  EXPECT_TRUE(Shell::Get()->window_selector_controller()->IsSelecting());
+
+  wm::ActivateWindow(window3.get());
+  EXPECT_FALSE(split_view_controller()->IsSplitViewModeActive());
+  EXPECT_FALSE(Shell::Get()->window_selector_controller()->IsSelecting());
+}
+
 // Test the tab-dragging related functionalities in tablet mode. Tab(s) can be
 // dragged out of a window and then put in split view mode or merge into another
 // window.