Use tighter typing in editing: EditingStyle

Source/core/editing/RemoveFormatCommand.cpp

Index: Source/core/editing/RemoveFormatCommand.cpp
diff --git a/Source/core/editing/RemoveFormatCommand.cpp b/Source/core/editing/RemoveFormatCommand.cpp
index ee8696d606ac7d486b16f2513251576e4b74a799..20bf63161f2f9d8b6e279fe9c63ddbe287cb9e8d 100644
--- a/Source/core/editing/RemoveFormatCommand.cpp
+++ b/Source/core/editing/RemoveFormatCommand.cpp
@@ -87,7 +87,7 @@ void RemoveFormatCommand::doApply()
 
     // Get the default style for this editable root, it's the style that we'll give the
     // content that we're operating on.
-    Node* root = frame->selection().rootEditableElement();
+    Element* root = frame->selection().rootEditableElement();
     RefPtrWillBeRawPtr<EditingStyle> defaultStyle = EditingStyle::create(root);
 
     // We want to remove everything but transparent background.