Merge pull request #2775 from NaturalGIS/processing_fix_saga_default_…

…extent

[processing] remove wrong/non mandatory default extent for raster analysis

python/plugins/processing/algs/saga/SagaAlgorithm212.py

@@ -102,7 +102,7 @@ def defineCharacteristicsFromFile(self):
                 # An extent parameter that wraps 4 SAGA numerical parameters
                 self.extentParamNames = line[6:].strip().split(' ')
                 self.addParameter(ParameterExtent(self.OUTPUT_EXTENT,
-                                                  'Output extent', '0,1,0,1'))
+                                                  'Output extent', ''))
             else:
                 self.addOutput(getOutputFromString(line))
             line = lines.readline().strip('\n').strip()