TextEditors: Remove "optimization"

I couldn't find a situation where this code actually resulted in
performance improvement.

Change-Id: I7d905af36ef11dcba43030dc83670c3d1558f650
Reviewed-by: Erik Verbruggen <erik.verbruggen@digia.com>

src/plugins/texteditor/basetexteditor.cpp

@@ -4467,7 +4467,6 @@ void BaseTextEditorWidget::indentOrUnindent(bool doIndent)
     const TextEditor::TabSettings &tabSettings = d->m_document->tabSettings();
 
     QTextCursor cursor = textCursor();
-    maybeClearSomeExtraSelections(cursor);
     cursor.beginEditBlock();
 
     if (cursor.hasSelection()) {
@@ -4678,13 +4677,11 @@ void BaseTextEditorWidget::indentInsertedText(const QTextCursor &tc)
 
 void BaseTextEditorWidget::indent(QTextDocument *doc, const QTextCursor &cursor, QChar typedChar)
 {
-    maybeClearSomeExtraSelections(cursor);
     d->m_document->indenter()->indent(doc, cursor, typedChar, tabSettings());
 }
 
 void BaseTextEditorWidget::reindent(QTextDocument *doc, const QTextCursor &cursor)
 {
-    maybeClearSomeExtraSelections(cursor);
     d->m_document->indenter()->reindent(doc, cursor, tabSettings());
 }
 
@@ -5223,25 +5220,6 @@ QList<QTextEdit::ExtraSelection> BaseTextEditorWidget::extraSelections(ExtraSele
     return d->m_extraSelections[kind];
 }
 
-void BaseTextEditorWidget::maybeClearSomeExtraSelections(const QTextCursor &cursor)
-{
-    const int smallSelectionSize = 50 * 50;
-    if (cursor.selectionEnd() - cursor.selectionStart() < smallSelectionSize)
-        return;
-
-    d->m_extraSelections[UndefinedSymbolSelection].clear();
-    d->m_extraSelections[ObjCSelection].clear();
-    d->m_extraSelections[CodeWarningsSelection].clear();
-
-    QList<QTextEdit::ExtraSelection> all;
-    for (int i = 0; i < NExtraSelectionKinds; ++i) {
-        if (i == CodeSemanticsSelection || i == SnippetPlaceholderSelection)
-            continue;
-        all += d->m_extraSelections[i];
-    }
-    QPlainTextEdit::setExtraSelections(all);
-}
-
 QString BaseTextEditorWidget::extraSelectionTooltip(int pos) const
 {
     QList<QTextEdit::ExtraSelection> all;

src/plugins/texteditor/basetexteditor.h

@@ -490,8 +490,6 @@ protected:
      */
     virtual bool openLink(const Link &link, bool inNextSplit = false);
 
-    void maybeClearSomeExtraSelections(const QTextCursor &cursor);
-
     /*!
       Reimplement this function to change the default replacement text.
       */