function includeSchema(mReferencedScope) {
			if (!(sSchema in mReferencedScope)) {
				fnLog(WARNING, sUrl, " does not contain ", sSchema);
				return;
			}

			fnLog(DEBUG, "Including ", sSchema, " from ", sUrl);
			let bMerged = false;
			for (const sKey in mReferencedScope) {
				// $EntityContainer can be ignored; $Reference, $Version is handled above
				if (sKey[0] !== "$" && schema(sKey) === sSchema) {
					mScope[sKey] = mReferencedScope[sKey];
					if (that._doMergeAnnotations(mScope[sKey], mScope.$Annotations)) {
						bMerged = true;
					}
				}
			}
			if (bMerged) {
				that._changeAnnotations(mScope);
			}
		}
Returns the schema with the given namespace, or a promise which is resolved as soon as the
schema has been included, or <code>undefined</code> in case the schema is neither present nor
referenced.

@param {object} mScope
  The $metadata "JSON" of the root service
@param {string} sSchema
  A namespace, for example "foo.bar.", of a schema
@param {function} fnLog
  The log function
@returns {object|sap.ui.base.SyncPromise|undefined}
  The schema, or a promise which is resolved without details or rejected with an error, or
  <code>undefined</code>.
@throws {Error}
  If the schema has already been loaded and read from a different URI

@private