Fix some Qt container anti pattern

applets/notes/plugin/documenthandler.cpp

@@ -309,8 +309,10 @@ QStringList DocumentHandler::defaultFontSizes() const
 {
     // uhm... this is quite ugly
     QStringList sizes;
-    QFontDatabase db;
-    for (int size : db.standardSizes())
+    const QList<int> standardSizes = QFontDatabase::standardSizes();
+    sizes.reserve(standardSizes.count());
+    for (int size : standardSizes) {
         sizes.append(QString::number(size));
+    }
     return sizes;
 }

dataengines/comic/comicproviderwrapper.cpp

@@ -755,8 +755,8 @@ void ComicProviderWrapper::requestPage(const QString &url, int id, const QVarian
 {
     QMap<QString, QString> map;
 
-    for (const QString &key : infos.keys()) {
-        map[key] = infos[key].toString();
+    for (auto it = infos.begin(), end = infos.end(); it != end; ++it) {
+        map[it.key()] = it.value().toString();
     }
     mProvider->requestPage(QUrl(url), id, map);
     ++mRequests;
@@ -766,8 +766,8 @@ void ComicProviderWrapper::requestRedirectedUrl(const QString &url, int id, cons
 {
     QMap<QString, QString> map;
 
-    for (const QString &key : infos.keys()) {
-        map[key] = infos[key].toString();
+    for (auto it = infos.begin(), end = infos.end(); it != end; ++it) {
+        map[it.key()] = it.value().toString();
     }
     mProvider->requestRedirectedUrl(QUrl(url), id, map);
     ++mRequests;

runners/dictionary/dictionarymatchengine.cpp

@@ -78,8 +78,7 @@ void DictionaryMatchEngine::dataUpdated(const QString &source, const Plasma::Dat
     QString definition(result[QLatin1String("text")].toString());
 
     m_wordLock.lockForRead();
-    const auto values = m_lockers.values(source);
-    for (ThreadData *data : values) {
+    for (ThreadData *data : qAsConst(m_lockers)) {
         QMutexLocker locker(&data->mutex);
         /* Because of QString's CoW semantics, we don't have to worry about
          * the overhead of assigning this to every item. */