Process DisplaySnapshots in PlatformScreen.

services/ui/ws/display_manager.cc

Index: services/ui/ws/display_manager.cc
diff --git a/services/ui/ws/display_manager.cc b/services/ui/ws/display_manager.cc
index 70b3b58fec5e6884927d07160546737de4ba5808..1e35b74e4fa9de6a37f6485fb6743999992968d0 100644
--- a/services/ui/ws/display_manager.cc
+++ b/services/ui/ws/display_manager.cc
@@ -104,6 +104,14 @@ const Display* DisplayManager::GetDisplayContaining(
   return nullptr;
 }
 
+Display* DisplayManager::GetDisplayById(int64_t display_id) {

[rjkroege, 2016/08/30 18:41:59]

So: this display_id is a an id of a ui::Display right? which as we know is not
the same as the ws::Display. Right? So... this feels like a layering violation
to me.

[kylechar, 2016/08/31 15:58:01]

We're using the same id in all places.

+  for (Display* display : displays_) {
+    if (display->GetId() == display_id)
+      return display;
+  }
+  return nullptr;
+}
+
 const WindowManagerDisplayRoot* DisplayManager::GetWindowManagerDisplayRoot(
     const ServerWindow* window) const {
   const ServerWindow* last = window;
@@ -175,8 +183,10 @@ void DisplayManager::OnDisplayAdded(display::PlatformScreen* platform_screen,
 }
 
 void DisplayManager::OnDisplayRemoved(int64_t id) {
-  // TODO(kylechar): Implement.
-  NOTREACHED();
+  Display* display = GetDisplayById(id);

[rjkroege, 2016/08/30 18:41:59]

The PlatformDisplay should be the delegate and get told to destroy itself? It
will manage its storage yes?

[kylechar, 2016/08/31 15:58:01]

I'm not sure I agree/understand. Let's discuss at the meeting today.

I also copied and pasted this in from service.cc and wasn't paying enough
attention because I'm getting the display manager.. from the window server..
from the display manager. Fixed.

[kylechar, 2016/08/31 16:07:35]

Should have changed that comment. As per the discussion offline I understand
what you were saying.

+  if (display)
+    window_server_->display_manager()->DestroyDisplay(display);
+  // TODO(kylechar): What if the display is still pending?
 }
 
 void DisplayManager::OnDisplayModified(int64_t id, const gfx::Rect& bounds) {