Set coordinates on Bxy field before calling its setter

(because now communicate() is called in the setter)

tests/unit/test_extras.hxx

@@ -159,7 +159,6 @@ public:
     // Need some options for parallelTransform
     options = Options::getRoot();
     mpi = bout::globals::mpi;
-    source = static_cast<GridDataSource*>(new GridFromOptions(options));
   }
 
   void setCoordinates(std::shared_ptr<Coordinates> coords,
@@ -440,7 +439,6 @@ public:
         Field2D{1.0}, Field2D{1.0}, Field2D{1.0}, Field2D{1.0}, Field2D{0.0},
         Field2D{0.0}, Field2D{0.0}, Field2D{1.0}, Field2D{1.0}, Field2D{1.0},
         Field2D{0.0}, Field2D{0.0}, Field2D{0.0}, Field2D{0.0}, Field2D{0.0});
-    static_cast<FakeMesh*>(bout::globals::mesh)->setCoordinates(test_coords);
 
 
     // Set nonuniform corrections
@@ -451,6 +449,7 @@ public:
 #if BOUT_USE_METRIC_3D
 
     FieldMetric mutable_Bxy = test_coords->Bxy();
+    static_cast<FakeMesh*>(mutable_Bxy.getMesh())->setCoordinates(test_coords);
     mutable_Bxy.splitParallelSlices();
     test_coords->setBxy(mutable_Bxy);