Use gst_element_class_set_details_simple() instead. If you want to
convert automatically, here's a script:
for file in `git grep -l GstElementDetails`; do
sed -i -n -r '
1h
1!H
$ {
g
s/((\/\*[^\n]*\*\/)?\n)*[^\n]*GstElementDetails .* =\s*GST_ELEMENT_DETAILS\s*\((\"[^\"]*\",\s*\"[^\"]*\",\s*\"[^\"]*\",\s*(\"[^\"]*\"\s*)*)\);\n*(.*)gst_element_class_set_details \(([^,]*),\s*[^)]*\)/\n\n\5gst_element_class_set_details_simple (\6, \3)/
s/((\/\*[^\n]*\*\/)?\n)*[^\n]*GstElementDetails .* =\s*\{\s*(\"[^\"]*\",\s*\"[^\"]*\",\s*\"[^\"]*\",\s*(\"[^\"]*\"\s*)*)\};\n*(.*)gst_element_class_set_details \(([^,]*),\s*[^)]*\)/\n\n\5gst_element_class_set_details_simple (\6, \3)/
p
}' $file
~/gst/gstreamer/tools/gst-indent $file
done