Improve stability of test_studio_outline tests.

STUD-2084

common/test/acceptance/pages/studio/container.py

@@ -55,6 +55,15 @@ class ContainerPage(PageObject):
             Promise(_is_finished_loading, 'Finished rendering the xblock wrappers.').fulfill()
         )
 
+    def wait_for_component_menu(self):
+        """
+        Waits until the menu bar of components is present on the page.
+        """
+        EmptyPromise(
+            lambda: self.q(css='div.add-xblock-component').present,
+            'Wait for the menu of components to be present'
+        ).fulfill()
+
     @property
     def xblocks(self):
         """

common/test/acceptance/pages/studio/overview.py

@@ -345,7 +345,7 @@ class CourseOutlinePage(CoursePage, CourseOutlineContainer):
     BOTTOM_ADD_SECTION_BUTTON = '.outline > .add-section .button-new'
 
     def is_browser_on_page(self):
-        return self.q(css='body.view-outline').present
+        return self.q(css='body.view-outline').present and self.q(css='div.ui-loading.is-hidden').present
 
     def view_live(self):
         """

common/test/acceptance/pages/studio/utils.py

@@ -69,6 +69,7 @@ def add_discussion(page, menu_index=0):
     menu_index specifies which instance of the menus should be used (based on vertical
     placement within the page).
     """
+    page.wait_for_component_menu()
     click_css(page, 'a>span.large-discussion-icon', menu_index)
 
 
@@ -80,6 +81,7 @@ def add_advanced_component(page, menu_index, name):
     placement within the page).
     """
     # Click on the Advanced icon.
+    page.wait_for_component_menu()
     click_css(page, 'a>span.large-advanced-icon', menu_index, require_notification=False)
 
     # This does an animation to hide the first level of buttons