Basic display management for mus

components/mus/ws/platform_display.h

Index: components/mus/ws/platform_display.h
diff --git a/components/mus/ws/platform_display.h b/components/mus/ws/platform_display.h
index e293dbc38e4409b4fd4d69b03ba87ef4552d750c..f41dfc4031337d1ef8f872299a277c10d54c261f 100644
--- a/components/mus/ws/platform_display.h
+++ b/components/mus/ws/platform_display.h
@@ -21,6 +21,9 @@
 #include "components/mus/ws/platform_display_delegate.h"
 #include "components/mus/ws/platform_display_init_params.h"
 #include "mojo/public/cpp/bindings/callback.h"
+#include "ui/display/types/display_snapshot.h"
+#include "ui/display/types/native_display_delegate.h"
+#include "ui/display/types/native_display_observer.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/platform_window/platform_window_delegate.h"
 
@@ -107,7 +110,8 @@ class PlatformDisplay {
 // PlatformDisplay implementation that connects to the services necessary to
 // actually display.
 class DefaultPlatformDisplay : public PlatformDisplay,
-                               public ui::PlatformWindowDelegate {
+                               public ui::PlatformWindowDelegate,
+                               public ui::NativeDisplayObserver {
  public:
   explicit DefaultPlatformDisplay(const PlatformDisplayInitParams& init_params);
   ~DefaultPlatformDisplay() override;
@@ -129,6 +133,13 @@ class DefaultPlatformDisplay : public PlatformDisplay,
   void RequestCopyOfOutput(
       scoped_ptr<cc::CopyOutputRequest> output_request) override;
 
+  // ui::NativeDisplayObserver:
+  void OnConfigurationChanged() override;
+
+  // Additional display management callbacks.

[sky, 2016/04/18 21:25:00]

Make these private?

[rjkroege, 2016/04/21 20:19:53]

Done.

+  void OnDisplaysAquired(const std::vector<ui::DisplaySnapshot*>& displays);
+  void OnDisplayConfigured(const gfx::Rect& bounds, bool success);
+
  private:
   void WantToDraw();
 
@@ -170,6 +181,16 @@ class DefaultPlatformDisplay : public PlatformDisplay,
   scoped_ptr<TopLevelDisplayClient> top_level_display_client_;
   scoped_ptr<ui::PlatformWindow> platform_window_;
 
+  // Flags used to keep track of the current state of display configuration.
+  // |is_configuring| is true if configuring the displays and starts false.
+  bool is_configuring_;
+  // If |is_configuring_| is true and another display configuration event
+  // happens, the event is deferred. |should_configure_| is set to true and a
+  // display configuration will be scheduled after the current one finishes.
+  // NB: events are handled once per vblank.
+  bool should_configure_;
+  scoped_ptr<ui::NativeDisplayDelegate> native_display_delegate_;
+
 #if !defined(OS_ANDROID)
   scoped_ptr<ui::CursorLoader> cursor_loader_;
 #endif