Allow for some branches we can't test.

android/src/toga_android/app.py

@@ -93,9 +93,10 @@ def onOptionsItemSelected(self, menuitem):
 
     def onPrepareOptionsMenu(self, menu):
         # If the main window doesn't have a toolbar, there's no preparation required;
-        # this is a simple main window, which can't have commands.
+        # this is a simple main window, which can't have commands. This can't be
+        # validated in the testbed, so it's marked no-cover.
         if not hasattr(self._impl.interface.main_window, "toolbar"):
-            return False
+            return False  # pragma: no cover
 
         menu.clear()
         itemid = 1  # 0 is the same as Menu.NONE.

android/src/toga_android/window.py

@@ -56,8 +56,9 @@ def close(self):  # pragma: no cover
         # closed, so the platform-specific close handling is never triggered.
         pass
 
-    def configure_titlebar(self):
-        # Hide the titlebar on a simple window.
+    def configure_titlebar(self):  # pragma: no cover
+        # Hide the titlebar on a simple window. The testbed can't create a simple
+        # window, so we can't test this.
         self.app.native.getSupportActionBar().hide()
 
     def set_app(self, app):

iOS/src/toga_iOS/container.py

@@ -153,12 +153,13 @@ def __init__(
     def height(self):
         return self.layout_native.bounds.size.height - self.top_offset
 
+    # The testbed app won't instantiate a simple app, so we can't test these properties
     @property
-    def top_offset(self):
+    def top_offset(self):  # pragma: no cover
         return UIApplication.sharedApplication.statusBarFrame.size.height
 
     @property
-    def title(self):
+    def title(self):  # pragma: no cover
         return self._title
 
     @title.setter
@@ -201,10 +202,6 @@ def __init__(
         # Set the controller's view to be the root content widget
         self.content_controller.view = self.native
 
-    @property
-    def height(self):
-        return self.layout_native.bounds.size.height - self.top_offset
-
     @property
     def top_offset(self):
         return (