Let the test for presence of root element be the first step.

SebDieBln · SebDieBln · commit ef4b5ead5a36 · 2015-11-21T20:36:21.000+01:00
diff --git a/src/core/qgsmaplayer.cpp b/src/core/qgsmaplayer.cpp
@@ -1147,8 +1147,15 @@ QString QgsMapLayer::loadNamedStyle( const QString &theURI, bool &theResultFlag
 
 bool QgsMapLayer::importNamedStyle( QDomDocument& myDocument, QString& myErrorMessage )
 {
+  QDomElement myRoot = myDocument.firstChildElement( "qgis" );
+  if ( myRoot.isNull() )
+  {
+    myErrorMessage = tr( "Root <qgis> element could not be found" );
+    return false;
+  }
+
   // get style file version string, if any
-  QgsProjectVersion fileVersion( myDocument.firstChildElement( "qgis" ).attribute( "version" ) );
+  QgsProjectVersion fileVersion( myRoot.attribute( "version" ) );
   QgsProjectVersion thisVersion( QGis::QGIS_VERSION );
 
   if ( thisVersion > fileVersion )
@@ -1164,15 +1171,6 @@ bool QgsMapLayer::importNamedStyle( QDomDocument& myDocument, QString& myErrorMe
     // styleFile.dump();
   }
 
-  // now get the layer node out and pass it over to the layer
-  // to deserialise...
-  QDomElement myRoot = myDocument.firstChildElement( "qgis" );
-  if ( myRoot.isNull() )
-  {
-    myErrorMessage = tr( "Root <qgis> element could not be found" );
-    return false;
-  }
-
   //Test for matching geometry type on vector layers when applying, if geometry type is given in the style
   if ( type() == QgsMapLayer::VectorLayer && !myRoot.firstChildElement( "layerGeometryType" ).isNull() )
   {
