--- a/editor/libeditor/TextEditor.cpp
+++ b/editor/libeditor/TextEditor.cpp
@@ -1179,17 +1179,17 @@ NS_IMETHODIMP
 TextEditor::CanDelete(bool* aCanDelete)
 {
   NS_ENSURE_ARG_POINTER(aCanDelete);
   *aCanDelete = IsModifiable() && CanCutOrCopy(ePasswordFieldAllowed);
   return NS_OK;
 }
 
 // Shared between OutputToString and OutputToStream
-NS_IMETHODIMP
+nsresult
 TextEditor::GetAndInitDocEncoder(const nsAString& aFormatType,
                                  uint32_t aFlags,
                                  const nsACString& aCharset,
                                  nsIDocumentEncoder** encoder)
 {
   nsresult rv = NS_OK;
 
   nsAutoCString formatType(NS_DOC_ENCODER_CONTRACTID_BASE);

--- a/editor/libeditor/TextEditor.h
+++ b/editor/libeditor/TextEditor.h
@@ -175,20 +175,20 @@ public:
 
 protected:
   virtual ~TextEditor();
 
   NS_IMETHOD InitRules();
   void BeginEditorInit();
   nsresult EndEditorInit();
 
-  NS_IMETHOD GetAndInitDocEncoder(const nsAString& aFormatType,
-                                  uint32_t aFlags,
-                                  const nsACString& aCharset,
-                                  nsIDocumentEncoder** encoder);
+  nsresult GetAndInitDocEncoder(const nsAString& aFormatType,
+                                uint32_t aFlags,
+                                const nsACString& aCharset,
+                                nsIDocumentEncoder** encoder);
 
   NS_IMETHOD CreateBR(nsIDOMNode* aNode, int32_t aOffset,
                       nsCOMPtr<nsIDOMNode>* outBRNode,
                       EDirection aSelect = eNone);
   already_AddRefed<Element> CreateBRImpl(nsCOMPtr<nsINode>* aInOutParent,
                                          int32_t* aInOutOffset,
                                          EDirection aSelect);
   nsresult CreateBRImpl(nsCOMPtr<nsIDOMNode>* aInOutParent,
@@ -196,20 +196,20 @@ protected:
                         nsCOMPtr<nsIDOMNode>* outBRNode,
                         EDirection aSelect);
 
   /**
    * Factored methods for handling insertion of data from transferables
    * (drag&drop or clipboard).
    */
   NS_IMETHOD PrepareTransferable(nsITransferable** transferable);
-  NS_IMETHOD InsertTextFromTransferable(nsITransferable* transferable,
-                                        nsIDOMNode* aDestinationNode,
-                                        int32_t aDestOffset,
-                                        bool aDoDeleteSelection);
+  nsresult InsertTextFromTransferable(nsITransferable* transferable,
+                                      nsIDOMNode* aDestinationNode,
+                                      int32_t aDestOffset,
+                                      bool aDoDeleteSelection);
 
   /**
    * Shared outputstring; returns whether selection is collapsed and resulting
    * string.
    */
   nsresult SharedOutputString(uint32_t aFlags, bool* aIsCollapsed,
                               nsAString& aResult);
 

--- a/editor/libeditor/TextEditorDataTransfer.cpp
+++ b/editor/libeditor/TextEditorDataTransfer.cpp
@@ -92,17 +92,17 @@ TextEditor::InsertTextAt(const nsAString
 
     nsresult rv = selection->Collapse(targetNode, targetOffset);
     NS_ENSURE_SUCCESS(rv, rv);
   }
 
   return InsertText(aStringToInsert);
 }
 
-NS_IMETHODIMP
+nsresult
 TextEditor::InsertTextFromTransferable(nsITransferable* aTransferable,
                                        nsIDOMNode* aDestinationNode,
                                        int32_t aDestOffset,
                                        bool aDoDeleteSelection)
 {
   nsresult rv = NS_OK;
   nsAutoCString bestFlavor;
   nsCOMPtr<nsISupports> genericDataObj;