Rework compositor touch hit testing

Source/core/rendering/RenderBoxModelObject.cpp

Index: Source/core/rendering/RenderBoxModelObject.cpp
diff --git a/Source/core/rendering/RenderBoxModelObject.cpp b/Source/core/rendering/RenderBoxModelObject.cpp
index 809d44c78e4bcc1cd621a90954b8d350fc564eca..73deaad418ccac04349c16c21b923a64c83ebd3c 100644
--- a/Source/core/rendering/RenderBoxModelObject.cpp
+++ b/Source/core/rendering/RenderBoxModelObject.cpp
@@ -2543,6 +2543,18 @@ void RenderBoxModelObject::setContinuation(RenderBoxModelObject* continuation)
     }
 }
 
+void RenderBoxModelObject::computeLayerHitTestRects(LayerHitTestRects& rects) const
+{
+    RenderLayerModelObject::computeLayerHitTestRects(rects);
+
+    // If there is a continuation then we need to consult it here, since this is
+    // the root of the tree walk and it wouldn't otherwise get picked up.
+    // Continuations should always be siblings in the tree, so any others should
+    // get picked up already by the tree walk.
+    if (continuation())
+        continuation()->computeLayerHitTestRects(rects);
+}
+
 RenderObject* RenderBoxModelObject::firstLetterRemainingText() const
 {
     if (!firstLetterRemainingTextMap)