mus: Use the new drag API to implement tab dragging in chrome.

ui/views/mus/native_widget_mus.cc

Index: ui/views/mus/native_widget_mus.cc
diff --git a/ui/views/mus/native_widget_mus.cc b/ui/views/mus/native_widget_mus.cc
index 9bed4cca17d179f1dc34a82c230db8139edd6ec4..0b3caf767dae7eb893275267c5348958e5090733 100644
--- a/ui/views/mus/native_widget_mus.cc
+++ b/ui/views/mus/native_widget_mus.cc
@@ -7,6 +7,7 @@
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/message_loop/message_loop.h"
+#include "base/run_loop.h"
 #include "base/threading/thread_task_runner_handle.h"
 #include "components/bitmap_uploader/bitmap_uploader.h"
 #include "components/mus/public/cpp/property_type_converters.h"
@@ -29,6 +30,7 @@
 #include "ui/base/view_prop.h"
 #include "ui/display/display.h"
 #include "ui/display/screen.h"
+#include "ui/display/screen.h"
 #include "ui/events/event.h"
 #include "ui/gfx/canvas.h"
 #include "ui/gfx/path.h"
@@ -328,7 +330,7 @@ SkBitmap AppIconFromDelegate(WidgetDelegate* delegate) {
   return app_icon.GetRepresentation(1.f).sk_bitmap();
 }
 
-// Handles acknowledgement of an input event, either immediately when a nested
+// Handles acknowledgment of an input event, either immediately when a nested
 // message loop starts, or upon destruction.
 class EventAckHandler : public base::MessageLoop::NestingObserver {
  public:
@@ -366,6 +368,13 @@ class EventAckHandler : public base::MessageLoop::NestingObserver {
   DISALLOW_COPY_AND_ASSIGN(EventAckHandler);
 };
 
+void OnMoveLoopEnd(bool* out_success,
+                   base::Closure quit_closure,
+                   bool in_success) {
+  *out_success = in_success;
+  quit_closure.Run();
+}
+
 }  // namespace
 
 class NativeWidgetMus::MusWindowObserver : public mus::WindowObserver {
@@ -804,14 +813,14 @@ void NativeWidgetMus::ViewRemoved(View* view) {
 // used safely in a world where we separate things with mojo. They should be
 // removed; not ported.
 void NativeWidgetMus::SetNativeWindowProperty(const char* name, void* value) {
-  // TODO(beng): push properties to mus::Window.
-  // NOTIMPLEMENTED();
+  native_window_properties_[name] = value;
 }
 
 void* NativeWidgetMus::GetNativeWindowProperty(const char* name) const {
-  // TODO(beng): pull properties to mus::Window.
-  // NOTIMPLEMENTED();
-  return nullptr;
+  auto it = native_window_properties_.find(name);
+  if (it == native_window_properties_.end())
+    return nullptr;
+  return it->second;
 }
 
 TooltipManager* NativeWidgetMus::GetTooltipManager() const {
@@ -1166,12 +1175,31 @@ Widget::MoveLoopResult NativeWidgetMus::RunMoveLoop(
     const gfx::Vector2d& drag_offset,
     Widget::MoveLoopSource source,
     Widget::MoveLoopEscapeBehavior escape_behavior) {
-  // NOTIMPLEMENTED();
-  return Widget::MOVE_LOOP_CANCELED;
+  ReleaseCapture();
+
+  base::MessageLoopForUI* loop = base::MessageLoopForUI::current();
+  base::MessageLoop::ScopedNestableTaskAllower allow_nested(loop);
+  base::RunLoop run_loop;
+
+  mus::mojom::MoveLoopSource mus_source =
+      source == Widget::MOVE_LOOP_SOURCE_MOUSE ?
+      mus::mojom::MoveLoopSource::MOUSE :
+      mus::mojom::MoveLoopSource::TOUCH;
+
+  bool success = false;
+  gfx::Point cursor_location =
+      display::Screen::GetScreen()->GetCursorScreenPoint();
+  window_->PerformWindowMove(
+      mus_source, cursor_location,
+      base::Bind(OnMoveLoopEnd, &success, run_loop.QuitClosure()));
+
+  run_loop.Run();
+
+  return success ? Widget::MOVE_LOOP_SUCCESSFUL : Widget::MOVE_LOOP_CANCELED;
 }
 
 void NativeWidgetMus::EndMoveLoop() {
-  // NOTIMPLEMENTED();
+  window_->CancelWindowMove();
 }
 
 void NativeWidgetMus::SetVisibilityChangedAnimationsEnabled(bool value) {
@@ -1345,6 +1373,17 @@ void NativeWidgetMus::OnGestureEvent(ui::GestureEvent* event) {
   native_widget_delegate_->OnGestureEvent(event);
 }
 
+void NativeWidgetMus::OnHostResized(const aura::WindowTreeHost* host) {

[sky, 2016/06/30 23:23:54]

How come both this and NativeWidgetMus::OnBoundsChanged() call to
OnNativeWidgetSize/Move? Shouldn't only one be necessary?

[Elliot Glaysher, 2016/07/01 00:09:58]

I changed it, didn't notice any problems locally and I'm throwing it at the
trybots to see if it breaks anything.

(I'll also note that NativeWidgetMus used to similar like NativeWidgetAura,
which didn't implement much of the WindowTreeObserver interface and instead used
OnBoundsChanged() and friends for messaging. It now is more like
DesktopNativeWidgetAura, which uses OnHost{Resized,Moved}() and has an empty
OnBOundsChanged() implementation.)

+  gfx::Rect new_bounds = gfx::Rect(host->window()->bounds().size());
+  content_->SetBounds(new_bounds);
+  native_widget_delegate_->OnNativeWidgetSizeChanged(new_bounds.size());
+}
+
+void NativeWidgetMus::OnHostMoved(const aura::WindowTreeHost* host,
+                                  const gfx::Point& new_origin) {
+  native_widget_delegate_->OnNativeWidgetMove();
+}
+
 void NativeWidgetMus::OnHostCloseRequested(const aura::WindowTreeHost* host) {
   GetWidget()->Close();
 }