chore(doc-gen): ensure log is injected into getExportDocType

See angular#2446

Author: petebacondarwin

docs/dgeni-package/services/tsParser/getExportDocType.js

@@ -1,6 +1,6 @@
 var ts = require('typescript');
 
-module.exports = function getExportDocType() {
+module.exports = function getExportDocType(log) {
 
  return function(symbol) {
  if(symbol.flags & ts.SymbolFlags.FunctionScopedVariable) {