Bug 1572375 - part 7: Get rid of HTMLEditRules::OnModifyDocument() r=m_kato

`HTMLEditRules::OnModifyDocument()` is same as just calling
`EditorBase::EnsureNoPaddingBRElementForEmptyEditor()` and
`EditorBase::MaybeCreatePaddingBRElementForEmptyEditor()` so that this patch
gets rid of the method, then, creates `HTMLEditor::OnModifyDocumentInternal()`
and makes it do same thing.

Differential Revision: https://phabricator.services.mozilla.com/D41161

--HG--
extra : moz-landing-system : lando

editor/libeditor/HTMLEditRules.cpp

@@ -11118,38 +11118,9 @@ void HTMLEditRules::DocumentModifiedWorker() {
   }
 
   RefPtr<HTMLEditor> htmlEditor(mHTMLEditor);
-  htmlEditor->OnModifyDocument();
-}
-
-void HTMLEditRules::OnModifyDocument() {
-  MOZ_ASSERT(mHTMLEditor);
-
-  AutoSafeEditorData setData(*this, *mHTMLEditor);
-
-  // DeleteNodeWithTransaction() below may cause a flush, which could destroy
-  // the editor
-  nsAutoScriptBlockerSuppressNodeRemoved scriptBlocker;
-
-  // Delete our padding <br> element for empty editor, if we have one, since
-  // the document might not be empty any more.
-  if (HTMLEditorRef().mPaddingBRElementForEmptyEditor) {
-    // A mutation event listener may recreate padding <br> element for empty
-    // editor again during the call of DeleteNodeWithTransaction().  So, move
-    // it first.
-    RefPtr<HTMLBRElement> paddingBRElement(
-        std::move(HTMLEditorRef().mPaddingBRElementForEmptyEditor));
-    DebugOnly<nsresult> rv = MOZ_KnownLive(HTMLEditorRef())
-                                 .DeleteNodeWithTransaction(*paddingBRElement);
-    NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
-                         "Failed to remove the padding <br> element");
-  }
-
-  // Try to recreate the padding <br> element for empty editor if needed.
-  nsresult rv = MOZ_KnownLive(HTMLEditorRef())
-                    .MaybeCreatePaddingBRElementForEmptyEditor();
-  NS_WARNING_ASSERTION(
-      rv != NS_ERROR_EDITOR_DESTROYED,
-      "The editor has been destroyed during creating a padding <br> element");
+  nsresult rv = htmlEditor->OnModifyDocument();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "HTMLEditor::OnModifyDocument() failed");
   Unused << rv;
 }
 

editor/libeditor/HTMLEditRules.h

@@ -136,13 +136,6 @@ class HTMLEditRules : public TextEditRules {
   void StartToListenToEditSubActions() { mListenerEnabled = true; }
   void EndListeningToEditSubActions() { mListenerEnabled = false; }
 
-  /**
-   * OnModifyDocument() is called when DocumentModifiedWorker() calls
-   * HTMLEditor::OnModifyDocument().  The caller guarantees that there
-   * is AutoEditActionDataSetter instance in the editor.
-   */
-  MOZ_CAN_RUN_SCRIPT void OnModifyDocument();
-
  protected:
   virtual ~HTMLEditRules() = default;
 

editor/libeditor/HTMLEditor.cpp

@@ -5267,22 +5267,42 @@ nsHTMLDocument* HTMLEditor::GetHTMLDocument() const {
   return doc->AsHTMLDocument();
 }
 
-void HTMLEditor::OnModifyDocument() {
-  MOZ_ASSERT(mRules);
-
-  RefPtr<HTMLEditRules> htmlRules = mRules->AsHTMLEditRules();
+nsresult HTMLEditor::OnModifyDocument() {
   if (IsEditActionDataAvailable()) {
-    htmlRules->OnModifyDocument();
-    return;
+    return OnModifyDocumentInternal();
   }
 
   AutoEditActionDataSetter editActionData(
       *this, EditAction::eCreatePaddingBRElementForEmptyEditor);
   if (NS_WARN_IF(!editActionData.CanHandle())) {
-    return;
+    return NS_ERROR_NOT_AVAILABLE;
   }
 
-  htmlRules->OnModifyDocument();
+  return OnModifyDocumentInternal();
+}
+
+nsresult HTMLEditor::OnModifyDocumentInternal() {
+  MOZ_ASSERT(IsEditActionDataAvailable());
+
+  // EnsureNoPaddingBRElementForEmptyEditor() below may cause a flush, which
+  // could destroy the editor
+  nsAutoScriptBlockerSuppressNodeRemoved scriptBlocker;
+
+  // Delete our padding <br> element for empty editor, if we have one, since
+  // the document might not be empty any more.
+  nsresult rv = EnsureNoPaddingBRElementForEmptyEditor();
+  NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
+                       "Failed to remove the padding <br> element");
+  if (NS_WARN_IF(rv == NS_ERROR_EDITOR_DESTROYED)) {
+    return rv;
+  }
+
+  // Try to recreate the padding <br> element for empty editor if needed.
+  rv = MaybeCreatePaddingBRElementForEmptyEditor();
+  NS_WARNING_ASSERTION(
+      rv != NS_ERROR_EDITOR_DESTROYED,
+      "The editor has been destroyed during creating a padding <br> element");
+  return rv;
 }
 
 }  // namespace mozilla

editor/libeditor/HTMLEditor.h

@@ -1092,7 +1092,7 @@ class HTMLEditor final : public TextEditor,
    * HTMLEditRules::OnModifyDocument() with AutoEditActionDataSetter
    * instance.
    */
-  MOZ_CAN_RUN_SCRIPT void OnModifyDocument();
+  MOZ_CAN_RUN_SCRIPT MOZ_MUST_USE nsresult OnModifyDocument();
 
  protected:  // Called by helper classes.
   virtual void OnStartToHandleTopLevelEditSubAction(
@@ -2538,6 +2538,11 @@ class HTMLEditor final : public TextEditor,
   static nsresult SlurpBlob(dom::Blob* aBlob, nsPIDOMWindowOuter* aWindow,
                             BlobReader* aBlobReader);
 
+  /**
+   * OnModifyDocumentInternal() is called by OnModifyDocument().
+   */
+  MOZ_CAN_RUN_SCRIPT MOZ_MUST_USE nsresult OnModifyDocumentInternal();
+
  protected:
   RefPtr<TypeInState> mTypeInState;
   RefPtr<ComposerCommandsUpdater> mComposerCommandsUpdater;