Move have_wheel_event_handlers to WebLayerTreeView.

cc/debug/debug_rect_history.cc

Index: cc/debug/debug_rect_history.cc
diff --git a/cc/debug/debug_rect_history.cc b/cc/debug/debug_rect_history.cc
index 5ac2b5d8b55368b84b0f1e71fb0a62a350e8f04b..33896f8c16640aa7815e31e9be93f333e1bb9113 100644
--- a/cc/debug/debug_rect_history.cc
+++ b/cc/debug/debug_rect_history.cc
@@ -14,6 +14,7 @@
 #include "cc/trees/damage_tracker.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_host_common.h"
+#include "cc/trees/layer_tree_impl.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 
 namespace cc {
@@ -180,7 +181,7 @@ void DebugRectHistory::SaveWheelEventHandlerRects(LayerImpl* layer) {
 }
 
 void DebugRectHistory::SaveWheelEventHandlerRectsCallback(LayerImpl* layer) {
-  if (!layer->have_wheel_event_handlers())
+  if (!layer->layer_tree_impl()->have_wheel_event_handlers())

[aelias_OOO_until_Jul13, 2016/01/27 23:55:46]

I guess we also want to check if the layer is the root scrolling layer for the
purposes of this kind of profiling rect (I believe for chrome://tracing)

[dtapuska, 2016/01/28 16:23:06]

SaveWheelEventHandlerRects is only called on the root rect. This is enabled via
the Renderer Setttings in the inspector; it shows a rect for where there are
wheel handlers and it should be the entire page.

     return;
 
   debug_rects_.push_back(