Use tighter typing in editing/

Source/core/editing/ApplyBlockElementCommand.h

Index: Source/core/editing/ApplyBlockElementCommand.h
diff --git a/Source/core/editing/ApplyBlockElementCommand.h b/Source/core/editing/ApplyBlockElementCommand.h
index 164dcc032f8323f9e1d4c6adc8b8af364e76de48..3589a7e963b828b043c567176cd899f263edfb63 100644
--- a/Source/core/editing/ApplyBlockElementCommand.h
+++ b/Source/core/editing/ApplyBlockElementCommand.h
@@ -42,14 +42,14 @@ protected:
     ApplyBlockElementCommand(Document&, const QualifiedName& tagName);
 
     virtual void formatSelection(const VisiblePosition& startOfSelection, const VisiblePosition& endOfSelection);
-    PassRefPtrWillBeRawPtr<Element> createBlockElement() const;
+    PassRefPtrWillBeRawPtr<HTMLElement> createBlockElement() const;
     const QualifiedName tagName() const { return m_tagName; }
 
     virtual void trace(Visitor*) OVERRIDE;
 
 private:
     virtual void doApply() OVERRIDE FINAL;
-    virtual void formatRange(const Position& start, const Position& end, const Position& endOfSelection, RefPtrWillBeRawPtr<Element>&) = 0;
+    virtual void formatRange(const Position& start, const Position& end, const Position& endOfSelection, RefPtrWillBeRawPtr<HTMLElement>&) = 0;
     void rangeForParagraphSplittingTextNodesIfNeeded(const VisiblePosition&, Position&, Position&);
     VisiblePosition endOfNextParagrahSplittingTextNodesIfNeeded(VisiblePosition&, Position&, Position&);