[Aura] Support always-on-top top level window.

views/widget/native_widget_aura.cc

Index: views/widget/native_widget_aura.cc
diff --git a/views/widget/native_widget_aura.cc b/views/widget/native_widget_aura.cc
index cb4eebafab360b2eb12f222ff2297c5b1f98a8f6..b7e2f456dc4eb9e0ff2d601e89c2363919f03311 100644
--- a/views/widget/native_widget_aura.cc
+++ b/views/widget/native_widget_aura.cc
@@ -144,6 +144,9 @@ void NativeWidgetAura::InitNativeWidget(const Widget::InitParams& params) {
     gfx::NativeView parent = params.GetParent();
     if (parent)
       parent->AddTransientChild(window_);
+    // SetAlwaysOnTop before SetParent so that always-on-top container is used.
+    if (params.keep_on_top)
+      SetAlwaysOnTop(true);

[oshima, 2011/11/08 23:34:24]

SetAlwaysOnTop(params.keep_on_top);

[xiyuan, 2011/11/09 17:42:18]

Done.

     window_->SetParent(NULL);
   }
   // TODO(beng): do this some other way.
@@ -418,8 +421,22 @@ bool NativeWidgetAura::IsActive() const {
 }
 
 void NativeWidgetAura::SetAlwaysOnTop(bool on_top) {
-  // http://crbug.com/102582
-  NOTIMPLEMENTED();
+  switch (window_->type()) {

[oshima, 2011/11/08 23:34:24]

I think we want the shell handle these cases, not in widget.

[xiyuan, 2011/11/09 17:42:18]

Code is removed. Set always-on-top property on menu and tooltip will be ignored.

+    case aura::WINDOW_TYPE_NORMAL:
+    case aura::WINDOW_TYPE_POPUP:
+      SetNativeWindowProperty(aura::kAlwaysOnTopKey,
+          reinterpret_cast<void*>(on_top));

[oshima, 2011/11/08 23:34:24]

window->SetIntProperty(aura::kAlwaysOnTopKey, on_top); is simpler.

[xiyuan, 2011/11/09 17:42:18]

Done.

+     break;
+    case aura::WINDOW_TYPE_MENU:
+    case aura::WINDOW_TYPE_TOOLTIP:
+      // Menu and tooptip has their own container and ignores always-on-top.
+      break;
+    default:
+      NOTREACHED() << "Window " << window_->id()
+                   << " of type " << window_->type()
+                   << " does not support always-on-top.";
+      break;
+  }
 }
 
 void NativeWidgetAura::Maximize() {