Delete empty mojo python package, and prefix all python packages with mojo_

mojo/python/tests/bindings_structs_unittest.py

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import math
 import unittest
 
 # pylint: disable=E0611,F0401
-import mojo.system
+import mojo_system
 
 # Generated files
 # pylint: disable=F0401
 import regression_tests_mojom
 import sample_import_mojom
 import sample_import2_mojom
 import sample_service_mojom
 
 
 class StructBindingsTest(unittest.TestCase):
@@ skipping 134 matching lines @@
     defaults_test.a21 = None
     defaults_test.a21 = sample_import_mojom.Point()
     with self.assertRaises(TypeError):
       defaults_test.a21 = 1
     with self.assertRaises(TypeError):
       defaults_test.a21 = sample_import2_mojom.Thing()
 
     # Handles
     foo_instance = sample_service_mojom.Foo()
     foo_instance.source = None
-    foo_instance.source = mojo.system.Handle()
+    foo_instance.source = mojo_system.Handle()
     with self.assertRaises(TypeError):
       foo_instance.source = 1
     with self.assertRaises(TypeError):
       foo_instance.source = object()
 
   def testConstructor(self):
     bar_instance = sample_service_mojom.Bar()
     foo_instance = sample_service_mojom.Foo(name="Foo",
                                             x=-1,
                                             y=5,
@@ skipping 33 matching lines @@
     with self.assertRaises(TypeError):
       p = sample_import_mojom.Point(c=0)
 
   def testCyclicDefinition(self):
     a = regression_tests_mojom.A()
     b = regression_tests_mojom.B()
     self.assertIsNone(a.b)
     self.assertIsNone(b.a)
     a.b = b
     self.assertIs(a.b, b)