Fix some Clazy detaching container warnings

(not all are valid, but at worst this flips some more
Q_FOREACH uses to c++11 for loops)

Author: nyalldawson

src/app/dwg/qgsdwgimportdialog.cpp

@@ -471,7 +471,7 @@ void QgsDwgImportDialog::on_buttonBox_accepted()
     QgsLayerTreeGroup *dwgGroup = QgisApp::instance()->layerTreeView()->layerTreeModel()->rootGroup()->addGroup( leLayerGroup->text() );
     Q_ASSERT( dwgGroup );
 
-    Q_FOREACH ( QString layer, layers.keys() )
+    Q_FOREACH ( const QString &layer, layers.keys() )
     {
       createGroup( dwgGroup, layer, QStringList( layer ), layers[layer] );
     }

src/app/dwg/qgsdwgimporter.cpp

@@ -2606,7 +2606,7 @@ bool QgsDwgImporter::expandInserts( QString &error )
     QTransform t;
     t.translate( p.x(), p.y() ).scale( xscale, yscale ).rotateRadians( angle );
 
-    Q_FOREACH ( QString name, QStringList() << "hatches" << "lines" << "polylines" << "texts" << "points" )
+    Q_FOREACH ( const QString &name, QStringList() << "hatches" << "lines" << "polylines" << "texts" << "points" )
     {
       OGRLayerH src = OGR_DS_ExecuteSQL( mDs, QString( "SELECT * FROM %1 WHERE block=%2" ).arg( name ).arg( handle ).toUtf8().constData(), nullptr, nullptr );
       if ( !src )

src/app/qgscrashreport.cpp

@@ -108,7 +108,7 @@ const QString QgsCrashReport::toHtml() const
   }
 
   QString report;
-  Q_FOREACH ( QString line, reportData )
+  Q_FOREACH ( const QString &line, reportData )
   {
     report += line + "<br>";
   }

src/app/qgsjoindialog.cpp

@@ -171,7 +171,8 @@ void QgsJoinDialog::joinedLayerChanged( QgsMapLayer *layer )
 
   mUseJoinFieldsSubset->setChecked( false );
   QStandardItemModel *subsetModel = new QStandardItemModel( this );
-  Q_FOREACH ( const QgsField &field, vLayer->fields() )
+  const QgsFields layerFields = vLayer->fields();
+  for ( const QgsField &field : layerFields )
   {
     QStandardItem *subsetItem = new QStandardItem( field.name() );
     subsetItem->setCheckable( true );

src/app/qgsmaplayerstyleguiutils.cpp

@@ -62,7 +62,7 @@ QList<QAction *> QgsMapLayerStyleGuiUtils::actionsUseStyle( QgsMapLayer *layer,
   bool onlyOneStyle = mgr->styles().count() == 1;
 
   QList<QAction *> actions;
-  Q_FOREACH ( QString name, mgr->styles() )
+  Q_FOREACH ( const QString &name, mgr->styles() )
   {
     bool active = name == mgr->currentStyle();
     QAction *actionUse = new QAction( name, parent );

src/core/composer/qgscomposerattributetablev2.cpp

@@ -201,7 +201,8 @@ void QgsComposerAttributeTableV2::resetColumns()
 
   //rebuild columns list from vector layer fields
   int idx = 0;
-  Q_FOREACH ( const QgsField &field, source->fields() )
+  const QgsFields sourceFields = source->fields();
+  for ( const auto &field : sourceFields )
   {
     QString currentAlias = source->attributeDisplayName( idx );
     QgsComposerTableColumn *col = new QgsComposerTableColumn;
@@ -319,7 +320,7 @@ void QgsComposerAttributeTableV2::setDisplayedFields( const QStringList &fields,
   qDeleteAll( mColumns );
   mColumns.clear();
 
-  QgsFields layerFields = source->fields();
+  const QgsFields layerFields = source->fields();
 
   if ( !fields.isEmpty() )
   {
@@ -340,7 +341,7 @@ void QgsComposerAttributeTableV2::setDisplayedFields( const QStringList &fields,
   {
     //resetting, so add all attributes to columns
     int idx = 0;
-    Q_FOREACH ( const QgsField &field, layerFields )
+    for ( const QgsField &field : layerFields )
     {
       QString currentAlias = source->attributeDisplayName( idx );
       QgsComposerTableColumn *col = new QgsComposerTableColumn;

src/core/providers/memory/qgsmemoryproviderutils.cpp

@@ -61,7 +61,7 @@ QgsVectorLayer *QgsMemoryProviderUtils::createMemoryLayer( const QString &name,
   {
     parts << QStringLiteral( "crs=" ) + crs.authid();
   }
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const auto &field : fields )
   {
     parts << QStringLiteral( "field=%1:%2" ).arg( field.name(), memoryLayerFieldType( field.type() ) );
   }

src/core/qgsattributetableconfig.cpp

@@ -80,7 +80,7 @@ void QgsAttributeTableConfig::update( const QgsFields &fields )
     }
   }
 
-  Q_FOREACH ( const QgsField &field, fields )
+  for ( const auto &field : fields )
   {
     if ( !columns.contains( field.name() ) )
     {

src/core/qgsdataitem.cpp

@@ -1135,10 +1135,8 @@ void QgsZipItem::init()
     // keys << "ogr" << "gdal";
     keys << QStringLiteral( "gdal" ) << QStringLiteral( "ogr" );
 
-    QStringList::const_iterator i;
-    for ( i = keys.begin(); i != keys.end(); ++i )
+    for ( const auto &k : qgsAsConst( keys ) )
     {
-      QString k( *i );
       QgsDebugMsgLevel( "provider " + k, 3 );
       // some providers hangs with empty uri (PostGIS) etc...
       // -> using libraries directly

src/core/qgsgml.cpp

@@ -603,7 +603,7 @@ void QgsGmlStreamingParser::startElement( const XML_Char *el, const XML_Char **a
   {
     QString currentTypename( QString::fromUtf8( pszLocalName, localNameLen ) );
     QMap< QString, LayerProperties >::const_iterator iter = mMapTypeNameToProperties.constFind( currentTypename );
-    if ( iter != mMapTypeNameToProperties.end() )
+    if ( iter != mMapTypeNameToProperties.constEnd() )
     {
       mFeatureTupleDepth = mParseDepth;
       mCurrentTypename = currentTypename;