splitview: Remove ToggleOverview at the end of some splitview tests.

This was needed previously at the end of some tests otherwise there will
be a memory leak. The introduction of SplitViewTestWindowDelegate makes
this not needed anymore.

Test: ash_unittests SplitView* with asan and without
Bug: 766725
Change-Id: I4e9754f541719fa23250ee7f691d345f5e58bdc5
Reviewed-on: https://chromium-review.googlesource.com/744291Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Reviewed-by: Mitsuru Oshima <oshima@chromium.org>
Commit-Queue: Sammie Quon <sammiequon@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512587}

ash/wm/overview/window_selector_unittest.cc

@@ -2153,11 +2153,6 @@ TEST_F(SplitViewWindowSelectorTest, WindowGridSizeWhileDraggingWithSplitView) {
   EXPECT_EQ(GetSplitViewRightWindowBounds(window1.get()), GetGridBounds());
   window_selector()->Drag(selector_item, center);
   EXPECT_EQ(GetSplitViewRightWindowBounds(window1.get()), GetGridBounds());
-
-  // TODO(sammiequon|xdai): Exit overview as a stop gap solution to avoid memory
-  // leak during shutdown. Fix and remove the ToggleOverview. See
-  // crbug.com/766725
-  ToggleOverview();
 }
 
 // Tests dragging a unsnappable window.
@@ -2557,11 +2552,6 @@ TEST_F(SplitViewWindowSelectorTest, SplitViewOverviewBothActiveTest) {
   EXPECT_NE(window1_bounds, window1_bounds_after_resize);
   EXPECT_NE(overview_grid_bounds, overview_grid_bounds_after_resize);
   EXPECT_NE(divider_bounds, divider_bounds_after_resize);
-
-  // TODO(sammiequon|xdai): Exit overview as a stop gap solution to avoid memory
-  // leak during shutdown. Fix and remove the ToggleOverview. See
-  // crbug.com/766725
-  ToggleOverview();
 }
 
 // Verify that selecting an unsnappable window while in split view works as

ash/wm/splitview/split_view_controller_unittest.cc

@@ -418,11 +418,6 @@ TEST_F(SplitViewControllerTest, EnterOverviewTest) {
   auto iter = std::find(windows.begin(), windows.end(),
                         split_view_controller()->GetDefaultSnappedWindow());
   EXPECT_TRUE(iter == windows.end());
-
-  // TODO(sammiequon|xdai): Exit overview as a stop gap solution to avoid memory
-  // leak during shutdown. Fix and remove the ToggleOverview. See
-  // crbug.com/766725
-  ToggleOverview();
 }
 
 // Tests that the split divider was created when the split view mode is active