Remove babelrc, transform using babel-core

tasks/transform-types.js

@@ -0,0 +1,31 @@
+/**
+ * @filedesc
+ * Transforms type comments in all source files to types that Closure Compiler
+ * understands.
+ */
+
+const glob = require('glob');
+const mkdirp = require('mkdirp').sync;
+const fs = require('fs');
+const path = require('path');
+const transform = require('babel-core').transformFileSync;
+
+const options = {
+  plugins: 'jsdoc-closure',
+  parserOpts: {
+    parser: 'recast'
+  },
+  generatorOpts: {
+    generator: 'recast'
+  }
+};
+
+const outDir = path.join('build', 'src-closure');
+
+glob('src/**/*.js', (err, matches) => {
+  matches.forEach(match => {
+    const out = path.join(outDir, path.relative('src', match));
+    mkdirp(path.dirname(out));
+    fs.writeFileSync(out, transform(match, options).code, 'utf-8');
+  });
+});