fixup! fixup! Make pip wheel cache what it built

Author: sbidoul

src/pip/_internal/wheel.py

@@ -1170,9 +1170,6 @@ def build(
                     python_tag=python_tag,
                 )
                 if wheel_file:
-                    self.wheel_filenames.append(
-                        os.path.relpath(wheel_file, output_dir)
-                    )
                     if should_unpack:
                         # XXX: This is mildly duplicative with prepare_files,
                         # but not close enough to pull out to a single common
@@ -1212,6 +1209,9 @@ def build(
                             )
                             build_failure.append(req)
                             continue
+                    self.wheel_filenames.append(
+                        os.path.relpath(wheel_file, output_dir)
+                    )
                     build_success.append(req)
                 else:
                     build_failure.append(req)