Prune CreateVisibleSelectionDeprecated from unit test files

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 756c5470228adf5f54ccbc89355861dc351778bd..f63e2c9621d7c4b342b83bceff064fa1c696444f 100644
--- a/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
+++ b/third_party/WebKit/Source/core/editing/VisibleSelection.cpp
@@ -172,6 +172,7 @@ VisibleSelection createVisibleSelection(const Position& base, const Position& ex
 {
     DCHECK(!needsLayoutTreeUpdate(base));
     DCHECK(!needsLayoutTreeUpdate(extent));
+    DCHECK(base.isNotNull() || extent.isNull());
     return VisibleSelection::create(base, extent, affinity, isDirectional);
 }
 
@@ -191,6 +192,7 @@ VisibleSelection createVisibleSelection(const VisiblePosition& base, const Visib
 {
     DCHECK(base.isValid());
     DCHECK(extent.isValid());
+    DCHECK(base.isNotNull() || extent.isNull());
     return VisibleSelection::create(base.deepEquivalent(), extent.deepEquivalent(), base.affinity(), isDirectional);
 }
 
@@ -211,6 +213,7 @@ VisibleSelectionInFlatTree createVisibleSelection(const PositionInFlatTree& base
 {
     DCHECK(!needsLayoutTreeUpdate(base));
     DCHECK(!needsLayoutTreeUpdate(extent));
+    DCHECK(base.isNotNull() || extent.isNull());
     return VisibleSelectionInFlatTree::create(base, extent, affinity, isDirectional);
 }
 
@@ -230,6 +233,7 @@ VisibleSelectionInFlatTree createVisibleSelection(const VisiblePositionInFlatTre
 {
     DCHECK(base.isValid());
     DCHECK(extent.isValid());
+    DCHECK(base.isNotNull() || extent.isNull());
     return VisibleSelectionInFlatTree::create(base.deepEquivalent(), extent.deepEquivalent(), base.affinity(), isDirectional);
 }