Revert of cc: Add occlusion checker as a fixed view of occlusion tracker.

cc/layers/picture_layer_impl_unittest.cc

Index: cc/layers/picture_layer_impl_unittest.cc
diff --git a/cc/layers/picture_layer_impl_unittest.cc b/cc/layers/picture_layer_impl_unittest.cc
index 3d8468acba49beee86e707cacb177dafb1680735..bd6a8f7f479f7fd466a466cfadcbf30597a07103 100644
--- a/cc/layers/picture_layer_impl_unittest.cc
+++ b/cc/layers/picture_layer_impl_unittest.cc
@@ -160,7 +160,7 @@
         maximum_animation_contents_scale;
     layer->draw_properties().screen_space_transform_is_animating =
         animating_transform_to_screen;
-    layer->UpdateTiles(Occlusion());
+    layer->UpdateTiles(NULL);
   }
   static void VerifyAllTilesExistAndHavePile(
       const PictureLayerTiling* tiling,
@@ -348,7 +348,7 @@
                                         resourceless_software_draw);
   active_layer_->draw_properties().visible_content_rect = viewport;
   active_layer_->draw_properties().screen_space_transform = transform;
-  active_layer_->UpdateTiles(Occlusion());
+  active_layer_->UpdateTiles(NULL);
 
   gfx::Rect viewport_rect_for_tile_priority_in_view_space =
       viewport_rect_for_tile_priority;
@@ -386,7 +386,7 @@
                                         resourceless_software_draw);
   active_layer_->draw_properties().visible_content_rect = viewport;
   active_layer_->draw_properties().screen_space_transform = transform;
-  active_layer_->UpdateTiles(Occlusion());
+  active_layer_->UpdateTiles(NULL);
 
   gfx::Transform screen_to_view(gfx::Transform::kSkipInitialization);
   bool success = transform_for_tile_priority.GetInverse(&screen_to_view);
@@ -447,7 +447,7 @@
                                         resourceless_software_draw);
   active_layer_->draw_properties().visible_content_rect = viewport;
   active_layer_->draw_properties().screen_space_transform = transform;
-  active_layer_->UpdateTiles(Occlusion());
+  active_layer_->UpdateTiles(NULL);
 
   gfx::Rect visible_rect_for_tile_priority =
       active_layer_->visible_rect_for_tile_priority();
@@ -475,7 +475,7 @@
                                         viewport,
                                         transform,
                                         resourceless_software_draw);
-  active_layer_->UpdateTiles(Occlusion());
+  active_layer_->UpdateTiles(NULL);
 
   visible_rect_for_tile_priority =
       gfx::ScaleToEnclosingRect(visible_rect_for_tile_priority, 2);
@@ -1508,7 +1508,7 @@
   time_ticks += base::TimeDelta::FromMilliseconds(200);
   host_impl_.SetCurrentBeginFrameArgs(
       CreateBeginFrameArgsForTesting(time_ticks));
-  pending_layer_->UpdateTiles(Occlusion());
+  pending_layer_->UpdateTiles(NULL);
 
   pending_layer_->MarkVisibleResourcesAsRequired();
 
@@ -3125,7 +3125,7 @@
                                         resourceless_software_draw);
   active_layer_->draw_properties().visible_content_rect = viewport;
   active_layer_->draw_properties().screen_space_transform = transform;
-  active_layer_->UpdateTiles(Occlusion());
+  active_layer_->UpdateTiles(NULL);
 
   gfx::Rect visible_rect_for_tile_priority =
       active_layer_->visible_rect_for_tile_priority();
@@ -3153,7 +3153,7 @@
                                         viewport,
                                         transform,
                                         resourceless_software_draw);
-  active_layer_->UpdateTiles(Occlusion());
+  active_layer_->UpdateTiles(NULL);
 
   visible_rect_for_tile_priority =
       gfx::ScaleToEnclosingRect(visible_rect_for_tile_priority, 2);