[pitivi] tests: Integrate previewer manager resetting in TestCase

[Alexandru Băluț <alexbalut src gnome org>]

commit 3b3b6b27c9100481974fad186c895c1c93196ebf
Author: Alexandru Băluț <alexandru balut gmail com>
Date:   Sun Feb 11 01:40:44 2018 +0100

    tests: Integrate previewer manager resetting in TestCase

 tests/common.py |   12 ++++++------
 1 files changed, 6 insertions(+), 6 deletions(-)
---
diff --git a/tests/common.py b/tests/common.py
index 3b2a3a9..9a65d9a 100644
--- a/tests/common.py
+++ b/tests/common.py
@@ -35,6 +35,8 @@ from pitivi import check
 from pitivi.application import Pitivi
 from pitivi.project import ProjectManager
 from pitivi.settings import GlobalSettings
+from pitivi.timeline.previewers import Previewer
+from pitivi.timeline.previewers import PreviewGeneratorManager
 from pitivi.timeline.timeline import TimelineContainer
 from pitivi.utils.loggable import Loggable
 from pitivi.utils.misc import path_from_uri
@@ -90,12 +92,6 @@ def create_pitivi(**settings):
 
 
 def create_timeline_container():
-    # TODO: Get rid of Previewer.manager.
-    from pitivi.timeline.previewers import Previewer
-    from pitivi.timeline.previewers import PreviewGeneratorManager
-    assert hasattr(Previewer, "manager")
-    Previewer.manager = PreviewGeneratorManager()
-
     app = create_pitivi_mock()
     project_manager = ProjectManager(app)
     project_manager.newBlankProject()
@@ -192,6 +188,10 @@ class TestCase(unittest.TestCase, Loggable):
 
         self.__zoom_level = Zoomable.getCurrentZoomLevel()
 
+        # TODO: Get rid of Previewer.manager.
+        assert hasattr(Previewer, "manager")
+        Previewer.manager = PreviewGeneratorManager()
+
     def tearDown(self):
         # don't barf gc info all over the console if we have already failed a
         # test case