Bug 1480055 - part 3: Create non-virtual method to set EditorBase::mAllowsTransactionsToChangeSelection r=m_kato

There is no non-virtual method to modify
EditorBase::mAllowsTransactionsToChangeSelection.  Therefore,
AutoTransactionsConserveSelection calls virtual method,
nsIEditor::SetShouldTxnSetSelection() twice (from both constructor and
destructor).  So, we should save this unnecessary cost.

MozReview-Commit-ID: B7TYGnGtuLB

--HG--
extra : rebase_source : 26ce77fb63a1967cca88b002cd65e1105477a63d

editor/libeditor/EditorBase.cpp

@@ -985,7 +985,7 @@ EditorBase::EndPlaceholderTransaction()
 NS_IMETHODIMP
 EditorBase::SetShouldTxnSetSelection(bool aShould)
 {
-  mAllowsTransactionsToChangeSelection = aShould;
+  MakeThisAllowTransactionsToChangeSelection(aShould);
   return NS_OK;
 }
 

editor/libeditor/EditorBase.h

@@ -1556,6 +1556,16 @@ protected: // May be called by friends.
     return mAllowsTransactionsToChangeSelection;
   }
 
+  /**
+   * MakeThisAllowTransactionsToChangeSelection() with true makes this editor
+   * allow transactions to change Selection.  Otherwise, i.e., with false,
+   * makes this editor not allow transactions to change Selection.
+   */
+  inline void MakeThisAllowTransactionsToChangeSelection(bool aAllow)
+  {
+    mAllowsTransactionsToChangeSelection = aAllow;
+  }
+
   nsresult HandleInlineSpellCheck(EditSubAction aEditSubAction,
                                   Selection& aSelection,
                                   nsINode* previousSelectedNode,

editor/libeditor/EditorUtils.h

@@ -581,14 +581,14 @@ public:
     if (mEditorBase) {
       mAllowedTransactionsToChangeSelection =
         mEditorBase->AllowsTransactionsToChangeSelection();
-      mEditorBase->SetShouldTxnSetSelection(false);
+      mEditorBase->MakeThisAllowTransactionsToChangeSelection(false);
     }
   }
 
   ~AutoTransactionsConserveSelection()
   {
     if (mEditorBase) {
-      mEditorBase->SetShouldTxnSetSelection(
+      mEditorBase->MakeThisAllowTransactionsToChangeSelection(
                      mAllowedTransactionsToChangeSelection);
     }
   }