Add DisplayCompositorTest.

services/ui/surfaces/display_compositor.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
 #define SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_
 
 #include <stdint.h>
 
+#include <unordered_map>
+#include <vector>
+
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "cc/ipc/display_compositor.mojom.h"
 #include "cc/surfaces/frame_sink_id.h"
 #include "cc/surfaces/local_frame_id.h"
 #include "cc/surfaces/surface_id.h"
 #include "cc/surfaces/surface_manager.h"
 #include "cc/surfaces/surface_observer.h"
 
 namespace cc {
 class SurfaceHittest;
 class SurfaceManager;
 }  // namespace cc
 
 namespace ui {
-
-class DisplayCompositorClient;
+namespace test {
+class DisplayCompositorTest;
+}
 
 // The DisplayCompositor object is an object global to the Window Server app
 // that holds the SurfaceServer and allocates new Surfaces namespaces.
 // This object lives on the main thread of the Window Server.
 // TODO(rjkroege, fsamuel): This object will need to change to support multiple
 // displays.
 class DisplayCompositor : public cc::SurfaceObserver,
                           public base::RefCounted<DisplayCompositor> {
  public:
   explicit DisplayCompositor(cc::mojom::DisplayCompositorClientPtr client);
 
   // TODO(fsamuel):  These methods should be behind a mojo interface.
   void AddRootSurfaceReference(const cc::SurfaceId& child_id);
   void AddSurfaceReference(const cc::SurfaceId& parent_id,
                            const cc::SurfaceId& child_id);
   void RemoveRootSurfaceReference(const cc::SurfaceId& child_id);
   void RemoveSurfaceReference(const cc::SurfaceId& parent_id,
                               const cc::SurfaceId& child_id);
 
   cc::SurfaceManager* manager() { return &manager_; }
 
+  void set_reference_manager_for_testing(
+      cc::SurfaceReferenceManager* reference_manager) {
+    reference_manager_ = reference_manager;
+  }
+
  private:
   friend class base::RefCounted<DisplayCompositor>;
+  friend class test::DisplayCompositorTest;
+
   virtual ~DisplayCompositor();
 
   // cc::SurfaceObserver implementation.
   void OnSurfaceCreated(const cc::SurfaceId& surface_id,
                         const gfx::Size& frame_size,
                         float device_scale_factor) override;
   void OnSurfaceDamaged(const cc::SurfaceId& surface_id,
                         bool* changed) override;
 
   cc::mojom::DisplayCompositorClientPtr client_;
   cc::SurfaceManager manager_;
+  cc::SurfaceReferenceManager* reference_manager_;

[Fady Samuel, 2016/11/18 20:18:24]

Can we avoid having two references to the same thing? SurfaceManager is a
SurfaceReferenceManager?

[kylechar, 2016/11/24 20:43:14]

Not easily, at least from what I can think of. We need the whole SurfaceManager
public API available from DisplayCompositor. Making all of SurfaceManager into
an interface doesn't sound ideal just to write tests a bit easier.

Alternatively I could write code to generate
SurfaceFactories/Surfaces/SurfaceIds for tests so the real SurfaceManager is
used. Again, that isn't perfect and results in more complicated tests.

+
+  // Local copy of top level root surface id, for convenience.
+  const cc::SurfaceId root_surface_id_;
 
   // SurfaceIds that have temporary references from top level root so they
   // aren't GC'd before DisplayCompositorClient can add a real reference. This
   // is basically a collection of surface ids, for example:
   //   cc::SurfaceId surface_id(key, value[index]);
   // The LocalFrameIds are stored in the order the surfaces are created in.
   std::unordered_map<cc::FrameSinkId,
                      std::vector<cc::LocalFrameId>,
                      cc::FrameSinkIdHash>
       temp_references_;
 
   DISALLOW_COPY_AND_ASSIGN(DisplayCompositor);
 };
 
 }  // namespace ui
 
 #endif  //  SERVICES_UI_SURFACES_DISPLAY_COMPOSITOR_H_