Route selection bounds updates through the compositor

cc/trees/layer_tree_host.h

Index: cc/trees/layer_tree_host.h
diff --git a/cc/trees/layer_tree_host.h b/cc/trees/layer_tree_host.h
index ef6e74fabe0d763f6e2e38678399b32484552449..1d23c6c7325698ef78a64aa07711c6539573b74c 100644
--- a/cc/trees/layer_tree_host.h
+++ b/cc/trees/layer_tree_host.h
@@ -27,6 +27,7 @@
 #include "cc/debug/micro_benchmark.h"
 #include "cc/debug/micro_benchmark_controller.h"
 #include "cc/input/input_handler.h"
+#include "cc/input/layer_selection_bound.h"
 #include "cc/input/scrollbar.h"
 #include "cc/input/top_controls_state.h"
 #include "cc/layers/layer_lists.h"
@@ -178,6 +179,9 @@ class CC_EXPORT LayerTreeHost {
     return outer_viewport_scroll_layer_.get();
   }
 
+  void RegisterSelection(const LayerSelectionBound& anchor,
+                         const LayerSelectionBound& focus);
+
   const LayerTreeSettings& settings() const { return settings_; }
 
   void SetDebugState(const LayerTreeDebugState& debug_state);
@@ -439,6 +443,9 @@ class CC_EXPORT LayerTreeHost {
   scoped_refptr<Layer> inner_viewport_scroll_layer_;
   scoped_refptr<Layer> outer_viewport_scroll_layer_;
 
+  LayerSelectionBound selection_anchor_;
+  LayerSelectionBound selection_focus_;
+
   SharedBitmapManager* shared_bitmap_manager_;
 
   ScopedPtrVector<SwapPromise> swap_promise_list_;