Converts most of WorkspaceLayoutManager tests to use common code

ash/test/ash_test_impl_aura.h

Index: ash/test/ash_test_impl_aura.h
diff --git a/ash/test/ash_test_impl_aura.h b/ash/test/ash_test_impl_aura.h
index c395899c37819bf33d53749261dc41625034243c..2740ba15d79948bc96df557c6748846040ff907f 100644
--- a/ash/test/ash_test_impl_aura.h
+++ b/ash/test/ash_test_impl_aura.h
@@ -28,10 +28,17 @@ class AshTestImplAura : public AshTestImpl {
       const gfx::Rect& bounds_in_screen,
       ui::wm::WindowType type,
       int shell_window_id) override;
+  std::unique_ptr<WindowOwner> CreateToplevelTestWindow(
+      const gfx::Rect& bounds_in_screen,
+      int shell_window_id) override;
   display::Display GetSecondaryDisplay() override;
   bool SetSecondaryDisplayPlacement(
       display::DisplayPlacement::Position position,
       int offset) override;
+  void ConfigureWidgetInitParamsForDisplay(
+      WmWindow* window,
+      views::Widget::InitParams* init_params) override;
+  void AddTransientChild(WmWindow* parent, WmWindow* window) override;
 
  private:
   std::unique_ptr<test::AshTestBase> ash_test_base_;