vs: do not add generated objects to project

VS2015 automatically picks up outputs from CustomBuild commands, which we
now use instead of CustomBuildStep commands, which do not get picked up
automatically.

mesonbuild/backend/vs2010backend.py

@@ -457,14 +457,14 @@ class Vs2010Backend(backends.Backend):
 
     @staticmethod
     def has_objects(objects, additional_objects, generated_objects):
-        # Ignore generated objects, those are automatically used by MSBuild for VS2010, because they are part of
-        # the CustomBuildStep Outputs.
+        # Ignore generated objects, those are automatically used by MSBuild because they are part of
+        # the CustomBuild Outputs.
         return len(objects) + len(additional_objects) > 0
 
     @staticmethod
     def add_generated_objects(node, generated_objects):
-        # Do not add generated objects to project file. Those are automatically used by MSBuild for VS2010, because
-        # they are part of the CustomBuildStep Outputs.
+        # Do not add generated objects to project file. Those are automatically used by MSBuild, because
+        # they are part of the CustomBuild Outputs.
         return
 
     @staticmethod

mesonbuild/backend/vs2015backend.py

@@ -23,14 +23,3 @@ class Vs2015Backend(Vs2010Backend):
         self.platform_toolset = 'v140'
         self.vs_version = '2015'
 
-    @staticmethod
-    def has_objects(objects, additional_objects, generated_objects):
-        # VS2015 requires generated objects to be added explicitly to the project file.
-        return len(objects) + len(additional_objects) + len(generated_objects) > 0
-
-    @staticmethod
-    def add_generated_objects(node, generated_objects):
-        # VS2015 requires generated objects to be added explicitly to the project file.
-        for s in generated_objects:
-            ET.SubElement(node, 'Object', Include=s)
-        return