Constify the rendering/ selection code

Source/core/rendering/InlineTextBox.cpp

Index: Source/core/rendering/InlineTextBox.cpp
diff --git a/Source/core/rendering/InlineTextBox.cpp b/Source/core/rendering/InlineTextBox.cpp
index b1352fcb62c8278fb0873ae7de8e6ab011309024..86560f9e1a872f4166440b310d396754a8b07a87 100644
--- a/Source/core/rendering/InlineTextBox.cpp
+++ b/Source/core/rendering/InlineTextBox.cpp
@@ -148,7 +148,7 @@ bool InlineTextBox::isSelected(int startPos, int endPos) const
     return (sPos < ePos);
 }
 
-RenderObject::SelectionState InlineTextBox::selectionState()
+RenderObject::SelectionState InlineTextBox::selectionState() const
 {
     RenderObject::SelectionState state = renderer().selectionState();
     if (state == RenderObject::SelectionStart || state == RenderObject::SelectionEnd || state == RenderObject::SelectionBoth) {
@@ -627,7 +627,7 @@ void InlineTextBox::paint(PaintInfo& paintInfo, const LayoutPoint& paintOffset,
         context->concatCTM(rotation(boxRect, Counterclockwise));
 }
 
-void InlineTextBox::selectionStartEnd(int& sPos, int& ePos)
+void InlineTextBox::selectionStartEnd(int& sPos, int& ePos) const
 {
     int startPos, endPos;
     if (renderer().selectionState() == RenderObject::SelectionInside) {