Out-of-line trace() methods of editing template types.

third_party/WebKit/Source/core/editing/VisibleSelection.cpp

Index: third_party/WebKit/Source/core/editing/VisibleSelection.cpp
diff --git a/third_party/WebKit/Source/core/editing/VisibleSelection.cpp b/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
index 597d6364ecced454d751de46af63834caf06792b..93a33918ea786837abb6554909c17aab4b78dc89 100644
--- a/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
@@ -778,6 +778,14 @@ bool VisibleSelectionTemplate<Strategy>::operator==(
   return equalSelectionsAlgorithm<Strategy>(*this, other);
 }
 
+template <typename Strategy>
+DEFINE_TRACE(VisibleSelectionTemplate<Strategy>) {
+  visitor->trace(m_base);
+  visitor->trace(m_extent);
+  visitor->trace(m_start);
+  visitor->trace(m_end);
+}
+
 #ifndef NDEBUG
 
 template <typename Strategy>