Limit visibility {Left,Right}BoundaryOfLine() to SelectionModifier only

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

Index: third_party/WebKit/Source/core/editing/VisibleUnits.cpp
diff --git a/third_party/WebKit/Source/core/editing/VisibleUnits.cpp b/third_party/WebKit/Source/core/editing/VisibleUnits.cpp
index 13445853caefe5f6236155a56191bba013d1b1d9..3e2484f8e54e686ead2e863588adec4cfa121e51 100644
--- a/third_party/WebKit/Source/core/editing/VisibleUnits.cpp
+++ b/third_party/WebKit/Source/core/editing/VisibleUnits.cpp
@@ -1940,20 +1940,6 @@ bool IsEndOfEditableOrNonEditableContent(
   return IsTextControlElement(next_position.DeepEquivalent().AnchorNode());
 }
 
-VisiblePosition LeftBoundaryOfLine(const VisiblePosition& c,
-                                   TextDirection direction) {
-  DCHECK(c.IsValid()) << c;
-  return direction == TextDirection::kLtr ? LogicalStartOfLine(c)
-                                          : LogicalEndOfLine(c);
-}
-
-VisiblePosition RightBoundaryOfLine(const VisiblePosition& c,
-                                    TextDirection direction) {
-  DCHECK(c.IsValid()) << c;
-  return direction == TextDirection::kLtr ? LogicalEndOfLine(c)
-                                          : LogicalStartOfLine(c);
-}
-
 static bool IsNonTextLeafChild(LayoutObject* object) {
   if (object->SlowFirstChild())
     return false;