manifest: Make include groups propagate to extend-project elements

Any groups specified to an include element should propagate to any
extend-project elements and then on to the projects.

Change-Id: I62b95689cc13660858564ae569cbfd095961ecc7
Reviewed-on: https://gerrit-review.googlesource.com/c/git-repo/+/525321
Tested-by: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Commit-Queue: Peter Kjellerstedt <peter.kjellerstedt@axis.com>
Reviewed-by: Gavin Mak <gavinmak@google.com>
Reviewed-by: Mike Frysinger <vapier@google.com>

tests/test_manifest_xml.py

@@ -488,6 +488,41 @@ class IncludeElementTests(ManifestParseTestCase):
                 # Check level2 proj group not removed.
                 self.assertIn("l2g1", proj.groups)
 
+    def test_group_levels_with_extend_project(self):
+        root_m = self.manifest_dir / "root.xml"
+        root_m.write_text(
+            """
+<manifest>
+  <remote name="test-remote" fetch="http://localhost" />
+  <default remote="test-remote" revision="refs/heads/main" />
+  <include name="man1.xml" groups="top-group1" />
+  <include name="man2.xml" groups="top-group2" />
+</manifest>
+"""
+        )
+        (self.manifest_dir / "man1.xml").write_text(
+            """
+<manifest>
+  <project name="project1" path="project1" />
+</manifest>
+"""
+        )
+        (self.manifest_dir / "man2.xml").write_text(
+            """
+<manifest>
+  <extend-project name="project1" groups="eg1" />
+</manifest>
+"""
+        )
+        include_m = manifest_xml.XmlManifest(str(self.repodir), str(root_m))
+        proj = include_m.projects[0]
+        # Check project has inherited group via project element.
+        self.assertIn("top-group1", proj.groups)
+        # Check project has inherited group via extend-project element.
+        self.assertIn("top-group2", proj.groups)
+        # Check project has set group via extend-project element.
+        self.assertIn("eg1", proj.groups)
+
     def test_allow_bad_name_from_user(self):
         """Check handling of bad name attribute from the user's input."""