Bug 1547730 - Define __hash__ for SandboxDependsFunction and CombinedDependsFunction so we can reference it as a dictionary key in py3 r=glandium

Differential Revision: https://phabricator.services.mozilla.com/D28111

--HG--
extra : moz-landing-system : lando

python/mozbuild/mozbuild/configure/__init__.py

@@ -78,6 +78,9 @@ class SandboxDependsFunction(object):
     def __eq__(self, other):
         raise ConfigureError('Cannot compare @depends functions.')
 
+    def __hash__(self):
+        return object.__hash__(self)
+
     def __ne__(self, other):
         raise ConfigureError('Cannot compare @depends functions.')
 
@@ -232,6 +235,9 @@ class CombinedDependsFunction(DependsFunction):
                 self._func is other._func and
                 set(self.dependencies) == set(other.dependencies))
 
+    def __hash__(self):
+        return object.__hash__(self)
+
     def __ne__(self, other):
         return not self == other