fix: remove the "Legacy Library" button if libraries v1 are disabled (openedx#35736)

Removes the "Legacy Library" button from the legacy Studio "new block" button array if Libraries v1 are disabled, either via waffle flag or via the ENABLE_CONTENT_LIBRARIES feature flag.

Author: pomegranited

cms/djangoapps/contentstore/views/component.py

@@ -26,7 +26,12 @@
 from common.djangoapps.xblock_django.api import authorable_xblocks, disabled_xblocks
 from common.djangoapps.xblock_django.models import XBlockStudioConfigurationFlag
 from cms.djangoapps.contentstore.helpers import is_unit
-from cms.djangoapps.contentstore.toggles import libraries_v2_enabled, use_new_problem_editor, use_new_unit_page
+from cms.djangoapps.contentstore.toggles import (
+    libraries_v1_enabled,
+    libraries_v2_enabled,
+    use_new_problem_editor,
+    use_new_unit_page,
+)
 from cms.djangoapps.contentstore.xblock_storage_handlers.view_handlers import load_services_for_studio
 from openedx.core.lib.xblock_utils import get_aside_from_xblock, is_xblock_aside
 from openedx.core.djangoapps.discussions.models import DiscussionsConfiguration
@@ -488,6 +493,8 @@ def _filter_disabled_blocks(all_blocks):
     Filter out disabled xblocks from the provided list of xblock names.
     """
     disabled_block_names = [block.name for block in disabled_xblocks()]
+    if not libraries_v1_enabled():
+        disabled_block_names.append('library')
     if not libraries_v2_enabled():
         disabled_block_names.append('library_v2')
         disabled_block_names.append('itembank')