[FIX] base: keep _get_asset for retro compatibility

Return of _get_assets has been altered with commit 9cd982b
We keep it for retro compatibility, but devs that override it before need to
override now _get_asset_node to be called correctly by t-call-asset.

odoo/addons/base/ir/ir_qweb/ir_qweb.py

@@ -174,7 +174,7 @@ def _compile_directive_call_assets(self, el, options):
                 value=ast.Call(
                     func=ast.Attribute(
                         value=ast.Name(id='self', ctx=ast.Load()),
-                        attr='_get_asset',
+                        attr='_get_asset_nodes',
                         ctx=ast.Load()
                     ),
                     args=[
@@ -286,13 +286,23 @@ def _compile_widget_options(self, el, directive_type):
 
     # method called by computing code
 
+    # compatibility to remove after v11 - DEPRECATED
+    @tools.conditional(
+        'xml' not in tools.config['dev_mode'],
+        tools.ormcache_context('xmlid', 'options.get("lang", "en_US")', 'css', 'js', 'debug', 'async', keys=("website_id",)),
+    )
+    def _get_asset(self, xmlid, options, css=True, js=True, debug=False, async=False, values=None):
+        files, remains = self._get_asset_content(xmlid, options)
+        asset = AssetsBundle(xmlid, files, remains, env=self.env)
+        return asset.to_html(css=css, js=js, debug=debug, async=async, url_for=(values or {}).get('url_for', lambda url: url))
+
     @tools.conditional(
         # in non-xml-debug mode we want assets to be cached forever, and the admin can force a cache clear
         # by restarting the server after updating the source code (or using the "Clear server cache" in debug tools)
         'xml' not in tools.config['dev_mode'],
         tools.ormcache_context('xmlid', 'options.get("lang", "en_US")', 'css', 'js', 'debug', 'async', keys=("website_id",)),
     )
-    def _get_asset(self, xmlid, options, css=True, js=True, debug=False, async=False, values=None):
+    def _get_asset_nodes(self, xmlid, options, css=True, js=True, debug=False, async=False, values=None):
         files, remains = self._get_asset_content(xmlid, options)
         asset = AssetsBundle(xmlid, files, env=self.env)
         remains = [node for node in remains if (css and node[0] == 'link') or (js and node[0] != 'link')]