Fix crash bugs of FramePainter.

ash/wm/frame_painter_unittest.cc

Index: ash/wm/frame_painter_unittest.cc
diff --git a/ash/wm/frame_painter_unittest.cc b/ash/wm/frame_painter_unittest.cc
index 8ce42eb8564e8099a09c2cc278a67ddce23e7190..b7f11f5e43dfea1092039209e56c63534fbf4d62 100644
--- a/ash/wm/frame_painter_unittest.cc
+++ b/ash/wm/frame_painter_unittest.cc
@@ -123,6 +123,33 @@ TEST_F(FramePainterTest, Basics) {
   EXPECT_EQ(0u, FramePainter::instances_->size());
 }
 
+TEST_F(FramePainterTest, CreateAndDeleteSingleWindow) {
+  // Ensure that creating/deleting a window works well and doesn't cause
+  // crashes.  See crbug.com/155634
+  scoped_ptr<Widget> widget(CreateTestWidget());
+  scoped_ptr<FramePainter> painter(new FramePainter);
+  ImageButton size(NULL);
+  ImageButton close(NULL);
+  painter->Init(
+      widget.get(), NULL, &size, &close, FramePainter::SIZE_BUTTON_MAXIMIZES);
+  widget->Show();
+
+  // We only have one window, so it should use a solo header.
+  EXPECT_TRUE(painter->UseSoloWindowHeader());
+
+  // Close the window.
+  widget.reset();

[James Cook, 2012/10/16 20:51:46]

Maybe after this line assert that the root window property has been cleared?

[Jun Mukai, 2012/10/16 21:11:45]

Done.

+
+  // Recreate another window again.
+  painter.reset(new FramePainter);
+  widget.reset(CreateTestWidget());
+
+  painter->Init(
+      widget.get(), NULL, &size, &close, FramePainter::SIZE_BUTTON_MAXIMIZES);
+  widget->Show();
+  EXPECT_TRUE(painter->UseSoloWindowHeader());
+}
+
 TEST_F(FramePainterTest, UseSoloWindowHeader) {
   // Create a widget and a painter for it.
   scoped_ptr<Widget> w1(CreateTestWidget());