[processing] restore Polygonize algorithm functionality (fix #8252)

python/plugins/processing/gdal/polygonize.py

@@ -27,12 +27,13 @@
 from PyQt4 import QtGui, QtCore
 
 from processing.core.GeoAlgorithm import GeoAlgorithm
-from processing.tools.system import *
 
 from processing.parameters.ParameterRaster import ParameterRaster
 from processing.parameters.ParameterString import ParameterString
 from processing.outputs.OutputVector import OutputVector
 
+from processing.tools.system import *
+
 from processing.gdal.GdalUtils import GdalUtils
 
 class polygonize(GeoAlgorithm):
@@ -56,7 +57,7 @@ def processAlgorithm(self, progress):
         arguments = []
         arguments.append(self.getParameterValue(polygonize.INPUT))
         arguments.append('-f')
-        arguments.append('"ESRI Shapefile"')
+        arguments.append('ESRI Shapefile')
         output = self.getOutputValue(polygonize.OUTPUT)
         arguments.append(output)
         arguments.append(QtCore.QFileInfo(output).baseName())