gram: docs

> ./reference/ecma-376/part1/schemas/dml-lockedCanvas.xsd

<?xml version="1.0" encoding="utf-8"?>
<xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema"
  xmlns="http://purl.oclc.org/ooxml/drawingml/lockedCanvas"
  xmlns:a="http://purl.oclc.org/ooxml/drawingml/main"
  xmlns:r="http://purl.oclc.org/ooxml/officeDocument/relationships" elementFormDefault="qualified"
  targetNamespace="http://purl.oclc.org/ooxml/drawingml/lockedCanvas">
  <xsd:import namespace="http://purl.oclc.org/ooxml/drawingml/main" schemaLocation="dml-main.xsd"/>
  <xsd:element name="lockedCanvas" type="a:CT_GvmlGroupShape"/>
</xsd:schema>