Hide windows which were visible in SplitView when new left/right windows are

specified.

BUG=409724
TEST=SplitViewcontrollerTest.SplitModeActivation

Review URL: https://codereview.chromium.org/573803003

Cr-Commit-Position: refs/heads/master@{#295158}

athena/wm/split_view_controller.cc

@@ -65,14 +65,9 @@ void SplitViewController::ActivateSplitMode(aura::Window* left,
   aura::Window::Windows windows = window_list_provider_->GetWindowList();
   aura::Window::Windows::reverse_iterator iter = windows.rbegin();
   if (state_ == ACTIVE) {
-    if (left_window_ == right)
-      left_window_ = left;
-    if (right_window_ == left)
-      right_window_ = right;
-
-    if (!left)
+    if (!left && left_window_ != right)
       left = left_window_;
-    if (!right)
+    if (!right && right_window_ != left)
       right = right_window_;
   }
 
@@ -94,6 +89,12 @@ void SplitViewController::ActivateSplitMode(aura::Window* left,
     }
   }
 
+  to_hide_.clear();
+  if (left_window_ && left_window_ != left && left_window_ != right)
+    to_hide_.push_back(left_window_);
+  if (right_window_ && right_window_ != left && right_window_ != right)
+    to_hide_.push_back(right_window_);
+
   SetState(ACTIVE);
   right_window_ = right;
   left_window_ = left;
@@ -229,6 +230,10 @@ void SplitViewController::OnAnimationCompleted() {
     return;
   UpdateLayout(false);
 
+  for (size_t i = 0; i < to_hide_.size(); ++i)
+    to_hide_[i]->Hide();
+  to_hide_.clear();
+
   if (state_ == INACTIVE) {
     left_window_ = NULL;
     right_window_ = NULL;

athena/wm/split_view_controller.h

@@ -105,6 +105,10 @@ class ATHENA_EXPORT SplitViewController
   // container_ coordinates (along the x axis).
   int separator_position_;
 
+  // Windows which should be hidden when the animation initiated by
+  // UpdateLayout() completes.
+  std::vector<aura::Window*> to_hide_;
+
   base::WeakPtrFactory<SplitViewController> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(SplitViewController);

athena/wm/split_view_controller_unittest.cc

@@ -46,6 +46,22 @@ class SplitViewControllerTest : public test::AthenaTestBase {
             second_topmost == controller->right_window());
   }
 
+  // Returns whether only the split view windows are visible.
+  bool OnlySplitViewWindowsVisible() const {
+    SplitViewController* controller = api_->GetSplitViewController();
+    DCHECK(controller->IsSplitViewModeActive());
+    aura::Window::Windows list =
+        api_->GetWindowListProvider()->GetWindowList();
+    for (aura::Window::Windows::const_iterator it = list.begin();
+         it != list.end(); ++it) {
+      bool in_split_view = (*it == controller->left_window() ||
+                            *it == controller->right_window());
+      if (in_split_view != (*it)->IsVisible())
+        return false;
+    }
+    return true;
+  }
+
   bool IsSplitViewAllowed() const {
     return api_->GetSplitViewController()->CanScroll();
   }
@@ -69,8 +85,11 @@ TEST_F(SplitViewControllerTest, SplitModeActivation) {
   for (size_t i = 0; i < kNumWindows; ++i) {
     scoped_ptr<aura::Window> window = CreateTestWindow(NULL, gfx::Rect());
     windows.push_back(window.release());
+    windows[i]->Hide();
   }
 
+  windows[kNumWindows - 1]->Show();
+
   SplitViewController* controller = api()->GetSplitViewController();
   ASSERT_FALSE(controller->IsSplitViewModeActive());
 
@@ -80,6 +99,7 @@ TEST_F(SplitViewControllerTest, SplitModeActivation) {
   EXPECT_EQ(windows[kNumWindows - 1], controller->left_window());
   EXPECT_EQ(windows[kNumWindows - 2], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 
   // Select the window that is currently on the left for the right panel. The
   // windows should switch.
@@ -87,11 +107,13 @@ TEST_F(SplitViewControllerTest, SplitModeActivation) {
   EXPECT_EQ(windows[kNumWindows - 2], controller->left_window());
   EXPECT_EQ(windows[kNumWindows - 1], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 
   controller->ActivateSplitMode(windows[kNumWindows - 1], NULL);
   EXPECT_EQ(windows[kNumWindows - 1], controller->left_window());
   EXPECT_EQ(windows[kNumWindows - 2], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 
   // Select one of the windows behind the stacks for the right panel. The window
   // on the left should remain unchanged.
@@ -99,21 +121,25 @@ TEST_F(SplitViewControllerTest, SplitModeActivation) {
   EXPECT_EQ(windows[kNumWindows - 1], controller->left_window());
   EXPECT_EQ(windows[0], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 
   controller->ActivateSplitMode(windows[1], NULL);
   EXPECT_EQ(windows[1], controller->left_window());
   EXPECT_EQ(windows[0], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 
   controller->ActivateSplitMode(windows[4], windows[5]);
   EXPECT_EQ(windows[4], controller->left_window());
   EXPECT_EQ(windows[5], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 
   controller->ActivateSplitMode(windows[0], NULL);
   EXPECT_EQ(windows[0], controller->left_window());
   EXPECT_EQ(windows[5], controller->right_window());
   EXPECT_TRUE(SplitViewWindowsTopmost());
+  EXPECT_TRUE(OnlySplitViewWindowsVisible());
 }
 
 TEST_F(SplitViewControllerTest, LandscapeOnly) {