build: update build doc

Author: abose

gulpfile.js/index.js

@@ -142,6 +142,8 @@ function makeJSDist() {
             preserveComments: function (node, comment) {
                 const text = (comment.value || "").trim();
 
+                // license headers should not end up in distribution as the license of dist depends on
+                // internal vs external builds. we strip every comment except with below flag.
                 // Preserve ONLY comments starting with "DONT_STRIP_MINIFY:"
                 return text.includes("DONT_STRIP_MINIFY:");
             }
@@ -588,12 +590,14 @@ const minifyablePaths = [
 
 function _minifyBrowserContextFile(fileContent) {
     const minified = terser.minify(fileContent, {
-        mangle: false,
+        mangle: true,
         compress: {
             unused: false
         },
         output: {
             comments: function(node, comment) {
+                // license headers should not end up in distribution as the license of dist depends on
+                // internal vs external builds. we strip every comment except with below flag.
                 const text = comment.value.trim();
                 return text.includes("DONT_STRIP_MINIFY:");
             }