[osx] make bringtofront work correctly for owned and modal windows.

native/Avalonia.Native/src/OSX/AvnView.mm

@@ -300,11 +300,6 @@
 
 - (void)mouseDown:(NSEvent *)event
 {
-    if(_parent != nullptr)
-    {
-        _parent->BringToFront();
-    }
-    
     _isLeftPressed = true;
     _lastMouseDownEvent = event;
     [self mouseEvent:event withType:LeftButtonDown];

native/Avalonia.Native/src/OSX/AvnWindow.mm

@@ -183,11 +183,6 @@
     return self;
 }
 
-- (void)mouseDown:(NSEvent *)event
-{
-    _parent->BringToFront();
-}
-
 - (BOOL)windowShouldClose:(NSWindow *)sender
 {
     auto window = dynamic_cast<WindowImpl*>(_parent.getRaw());
@@ -435,8 +430,10 @@
 
                     _parent->BaseEvents->RawMouseEvent(NonClientLeftButtonDown, static_cast<uint32>([event timestamp] * 1000), AvnInputModifiersNone, point, delta);
                 }
+                
+                _parent->BringToFront();
             }
-                break;
+            break;
 
             case NSEventTypeMouseEntered:
             {

native/Avalonia.Native/src/OSX/WindowImpl.mm

@@ -126,7 +126,14 @@ HRESULT WindowImpl::SetParent(IAvnWindow *parent) {
 
 void WindowImpl::BringToFront()
 {
-    Activate();
+    if(IsDialog())
+    {
+        Activate();
+    }
+    else
+    {
+        [Window orderFront:nullptr];
+    }
     
     for(auto iterator = _children.begin(); iterator != _children.end(); iterator++)
     {