[TIMOB-15590] Titanium.Utils.base64decode truncates result with foreign characters

Problem description

Titanium.Utils.base64encode generates a truncated blob when operating on Chinese characters.

Code sample:

var original = '一些随机的中国文字';
var reference = '5LiA5Lqb6ZqP5py655qE5Lit5Zu95paH5a2X';
var encoded = Titanium.Utils.base64encode(original).text;
console.log('encoded: ' + encoded);
console.log('reference: ' + reference);
console.log('encoded ' + (encoded === reference ? '===' : '!==') + ' reference');

Steps to reproduce

1. Create a new mobile project 2. Paste this to app.js: 3. Run and check the console.

Output:

{noformat} encoded: 5LiA5Lqb6ZqP reference: 5LiA5Lqb6ZqP5py655qE5Lit5Zu95paH5a2X encoded !== reference {noformat}

Expected output:

{noformat} encoded: 5LiA5Lqb6ZqP5py655qE5Lit5Zu95paH5a2X reference: 5LiA5Lqb6ZqP5py655qE5Lit5Zu95paH5a2X encoded === reference {noformat} When "original" is Base64-encoded, the result should be equal to "reference". However, the blob returned by Titanium.Utils.base64encode is significantly shorter than expected. Titanium.Utils.base64encode apparently cannot properly handle special characters.