I18n: make presets translatable

Presets are used all over the Blender UI, but were so far untranslatable.

This adds the translation code as well as a new `dump_preset_messages()` function in the message extraction. This goes over all bundled preset file names and extracts them.

Reviewed By: mont29

Differential Revision: https://developer.blender.org/D15570

release/scripts/modules/bl_i18n_utils/bl_extract_messages.py

@@ -853,6 +853,25 @@ def dump_src_messages(msgs, reports, settings):
             dump_src_file(path, rel_path, msgs, reports, settings)
 
 
+def dump_preset_messages(msgs, reports, settings):
+    files = []
+    for dpath, _, fnames in os.walk(settings.PRESETS_DIR):
+        for fname in fnames:
+            if fname.startswith("_") or not fname.endswith(".py"):
+                continue
+            path = os.path.join(dpath, fname)
+            try:  # can't always find the relative path (between drive letters on windows)
+                rel_path = os.path.relpath(path, settings.PRESETS_DIR)
+            except ValueError:
+                rel_path = path
+            files.append(rel_path)
+    for rel_path in files:
+        msgsrc, msgid = os.path.split(rel_path)
+        msgsrc = "Preset from " + msgsrc
+        msgid = bpy.path.display_name(msgid, title_case=False)
+        process_msg(msgs, settings.DEFAULT_CONTEXT, msgid, msgsrc, reports, None, settings)
+
+
 ##### Main functions! #####
 def dump_messages(do_messages, do_checks, settings):
     bl_ver = "Blender " + bpy.app.version_string
@@ -885,6 +904,9 @@ def dump_messages(do_messages, do_checks, settings):
     # Get strings from C source code.
     dump_src_messages(msgs, reports, settings)
 
+    # Get strings from presets.
+    dump_preset_messages(msgs, reports, settings)
+
     # Get strings from addons' categories.
     for uid, label, tip in bpy.types.WindowManager.addon_filter.keywords['items'](
             bpy.context.window_manager,