cc: Pass Occlusion instead of OcclusionTracker to LayerImpls

cc/layers/heads_up_display_layer_impl_unittest.cc

Index: cc/layers/heads_up_display_layer_impl_unittest.cc
diff --git a/cc/layers/heads_up_display_layer_impl_unittest.cc b/cc/layers/heads_up_display_layer_impl_unittest.cc
index 828a93a42bb2649d483384a895cff3754b319c48..d342d4f70938c07540bf020b882f478710e8fbf0 100644
--- a/cc/layers/heads_up_display_layer_impl_unittest.cc
+++ b/cc/layers/heads_up_display_layer_impl_unittest.cc
@@ -7,7 +7,6 @@
 #include "cc/test/fake_impl_proxy.h"
 #include "cc/test/fake_layer_tree_host_impl.h"
 #include "cc/test/fake_output_surface.h"
-#include "cc/test/mock_occlusion_tracker.h"
 #include "cc/test/test_shared_bitmap_manager.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -17,12 +16,11 @@ namespace {
 void CheckDrawLayer(HeadsUpDisplayLayerImpl* layer,
                     ResourceProvider* resource_provider,
                     DrawMode draw_mode) {
-  MockOcclusionTracker<LayerImpl> occlusion_tracker;
   scoped_ptr<RenderPass> render_pass = RenderPass::Create();
   AppendQuadsData data;
   bool will_draw = layer->WillDraw(draw_mode, resource_provider);
   if (will_draw)
-    layer->AppendQuads(render_pass.get(), occlusion_tracker, &data);
+    layer->AppendQuads(render_pass.get(), Occlusion(), &data);
   layer->UpdateHudTexture(draw_mode, resource_provider);
   if (will_draw)
     layer->DidDraw(resource_provider);