Make DesktopWindowTreeHostX11::ShouldWindowContentsBeTransparent() relies on argb visual flag

ui/views/widget/widget_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 <algorithm>
 #include <memory>
 #include <set>
 
 #include "base/bind.h"
+#include "base/command_line.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "build/build_config.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/base/hit_test.h"
 #include "ui/compositor/layer_animation_observer.h"
 #include "ui/compositor/scoped_animation_duration_scale_mode.h"
 #include "ui/compositor/scoped_layer_animation_settings.h"
@@ skipping 20 matching lines @@
 #include "ui/aura/window_tree_host.h"
 #include "ui/base/view_prop.h"
 #include "ui/base/win/window_event_target.h"
 #include "ui/views/win/hwnd_util.h"
 #endif
 
 #if defined(OS_MACOSX)
 #include "base/mac/mac_util.h"
 #endif
 
+#if defined(USE_X11) && !defined(OS_CHROMEOS)
+#include "ui/base/x/x11_util_internal.h"  // nogncheck
+#include "ui/gfx/x/x11_switches.h"  // nogncheck
+#endif
+
 namespace views {
 namespace test {
 
 namespace {
 
 // TODO(tdanderson): This utility function is used in different unittest
 //                   files. Move to a common location to avoid
 //                   repeated code.
 gfx::Point ConvertPointFromWidgetToView(View* view, const gfx::Point& p) {
   gfx::Point tmp(p);
@@ skipping 3638 matching lines @@
 
   EXPECT_FALSE(!!IsWindow(owner_hwnd));
   EXPECT_FALSE(!!IsWindow(owned_hwnd));
   EXPECT_TRUE(!!IsWindowEnabled(top_hwnd));
 
   top_level_widget.CloseNow();
 }
 
 #endif  // defined(OS_WIN)
 
+#if !defined(OS_CHROMEOS)
+// Test to ensure that the transparency state of the native window maches
+// what returns ShouldWindowContentsBeTransparent(). On Linux it also checks
+// that it returns true when --enable-transparent-visuals is passed.
+TEST_F(WidgetTest, Transparency_DesktopWidget) {
+#if defined(USE_X11)
+  // On Linux, transparent visuals is currently not activated by default.
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  command_line->AppendSwitch(switches::kEnableTransparentVisuals);
+
+  int depth = 0;
+  ui::ChooseVisualForWindow(NULL, &depth);
+  EXPECT_EQ(depth, 32);
+#endif
+
+  Widget::InitParams init_params =
+      CreateParams(Widget::InitParams::TYPE_WINDOW);
+  init_params.show_state = ui::SHOW_STATE_NORMAL;
+  init_params.bounds = gfx::Rect(0, 0, 500, 500);
+  init_params.ownership = Widget::InitParams::WIDGET_OWNS_NATIVE_WIDGET;
+  Widget widget;
+  init_params.native_widget =
+      CreatePlatformDesktopNativeWidgetImpl(init_params, &widget, nullptr);
+  widget.Init(init_params);
+
+  EXPECT_EQ(IsNativeWindowTransparent(widget.GetNativeWindow()),
+            widget.ShouldWindowContentsBeTransparent());

[sadrul, 2016/06/14 15:45:31]

You should need to at least set Widget::InitParams::opacity to
TRANSLUCENT_WINDOW?

[Julien Isorce Samsung, 2016/06/14 16:02:40]

Yes you are right. Somehow the test still succeeds with default value
INFER_OPACITY and same with OPAQUE_WINDOW. (and with default value it seems to
succeed on all platforms)

+
+#if defined(USE_X11)
+  EXPECT_TRUE(widget.ShouldWindowContentsBeTransparent());
+#endif
+}
+#endif  // !defined(OS_CHROMEOS)
+
 }  // namespace test
 }  // namespace views