Check if the resizer has been deleted during drag start.

ash/wm/toplevel_window_event_handler_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "ash/wm/toplevel_window_event_handler.h"
 
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "ash/test/ash_test_base.h"
 #include "ash/wm/resize_shadow.h"
 #include "ash/wm/resize_shadow_controller.h"
 #include "ash/wm/window_state.h"
 #include "ash/wm/window_util.h"
 #include "ash/wm/workspace_controller.h"
 #include "base/compiler_specific.h"
 #include "base/thread_task_runner_handle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/aura/client/aura_constants.h"
+#include "ui/aura/client/capture_client.h"
 #include "ui/aura/test/aura_test_base.h"
 #include "ui/aura/test/test_window_delegate.h"
 #include "ui/aura/window_event_dispatcher.h"
 #include "ui/base/hit_test.h"
 #include "ui/events/event.h"
 #include "ui/events/test/event_generator.h"
 #include "ui/gfx/screen.h"
 #include "ui/wm/core/window_util.h"
 #include "ui/wm/public/window_move_client.h"
 
@@ skipping 30 matching lines @@
   ToplevelWindowEventHandlerTest() {}
   ~ToplevelWindowEventHandlerTest() override {}
 
  protected:
   aura::Window* CreateWindow(int hittest_code) {
     TestWindowDelegate* d1 = new TestWindowDelegate(hittest_code);
     aura::Window* w1 = new aura::Window(d1);
     w1->SetType(ui::wm::WINDOW_TYPE_NORMAL);
     w1->set_id(1);
     w1->Init(ui::LAYER_TEXTURED);
-    aura::Window* parent = Shell::GetContainer(
-        Shell::GetPrimaryRootWindow(), kShellWindowId_AlwaysOnTopContainer);
+    aura::Window* parent = Shell::GetContainer(Shell::GetPrimaryRootWindow(),
+                                               kShellWindowId_DefaultContainer);

[oshima, 2016/03/15 09:15:04]

This is is to use normal dragging path (window in AlwaysOnTop does not use
DockedWindowResizer). I'm changing this for all cases because it think it has
better coverage.

     parent->AddChild(w1);
     w1->SetBounds(gfx::Rect(0, 0, 100, 100));
     w1->Show();
     return w1;
   }
 
   void DragFromCenterBy(aura::Window* window, int dx, int dy) {
     ui::test::EventGenerator generator(Shell::GetPrimaryRootWindow(), window);
     generator.DragMouseBy(dx, dy);
   }
@@ skipping 20 matching lines @@
   // Size should not have.
   EXPECT_EQ(size.ToString(), w1->bounds().size().ToString());
 
   TouchDragFromCenterBy(w1.get(), 100, 100);
   // Position should have been offset by 100,100.
   EXPECT_EQ("200,200", w1->bounds().origin().ToString());
   // Size should not have.
   EXPECT_EQ(size.ToString(), w1->bounds().size().ToString());
 }
 
+namespace {
+
+class CancelDragObserver : public aura::WindowObserver {
+ public:
+  CancelDragObserver() {}
+  ~CancelDragObserver() override {}
+
+  void OnWindowHierarchyChanging(const HierarchyChangeParams& params) override {
+    aura::client::CaptureClient* client =
+        aura::client::GetCaptureClient(params.target->GetRootWindow());
+    client->SetCapture(nullptr);
+  }
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(CancelDragObserver);
+};
+
+}  // namespace
+
+// Cancelling drag while starting window drag should not crash.
+TEST_F(ToplevelWindowEventHandlerTest, CancelWhileDragStart) {
+  scoped_ptr<aura::Window> w1(CreateWindow(HTCAPTION));
+  CancelDragObserver observer;
+  w1->AddObserver(&observer);
+  gfx::Point origin = w1->bounds().origin();
+  DragFromCenterBy(w1.get(), 100, 100);
+  EXPECT_EQ(origin, w1->bounds().origin());
+  w1->RemoveObserver(&observer);
+}
+
 TEST_F(ToplevelWindowEventHandlerTest, BottomRight) {
   scoped_ptr<aura::Window> w1(CreateWindow(HTBOTTOMRIGHT));
   gfx::Point position = w1->bounds().origin();
   DragFromCenterBy(w1.get(), 100, 100);
   // Position should not have changed.
   EXPECT_EQ(position.ToString(), w1->bounds().origin().ToString());
   // Size should have increased by 100,100.
   EXPECT_EQ(gfx::Size(200, 200).ToString(), w1->bounds().size().ToString());
 }
 
@@ skipping 628 matching lines @@
   EXPECT_EQ(aura::client::MOVE_SUCCESSFUL,
             move_client->RunMoveLoop(window.get(), gfx::Vector2d(),
                                      aura::client::WINDOW_MOVE_SOURCE_TOUCH));
 }
 
 // Showing the resize shadows when the mouse is over the window edges is tested
 // in resize_shadow_and_cursor_test.cc
 
 }  // namespace test
 }  // namespace ash