[patch] use binary encoding function that does not overflow

If the qr codes get too big (in total file size), then the current function will blow up. This one works better, tested manually by updating the dist/build.js, and updating example.html to point to that instead of the production cdn hosted websdk

Author: bredmond5

example.html

@@ -83,7 +83,6 @@ <h4>QR Code</h4>
 	<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
 	<script type="text/javascript">
 		(function(b,r,a,n,c,h,_,s,d,k){if(!b[n]||!b[n]._q){for(;s<_.length;)c(h,_[s++]);d=r.createElement(a);d.async=1;d.src="https://cdn.branch.io/branch-latest.min.js";k=r.getElementsByTagName(a)[0];k.parentNode.insertBefore(d,k);b[n]=h}})(window,document,"script","branch",function(b,r){b[r]=function(){b._q.push([r,arguments])}},{_q:[],_v:1},"addListener banner closeBanner closeJourney data deepview deepviewCta first init link logout removeListener setBranchViewData setIdentity track trackCommerceEvent logEvent disableTracking getBrowserFingerprintId crossPlatformIds lastAttributedTouchData setAPIResponseCallback qrCode setRequestMetaData setDMAParamsForEEA setAPIUrl getAPIUrl".split(" "), 0);
-		branch.setAPIUrl("https://api.stage.branch.io");
 
 		branch.setAPIResponseCallback(function(url, method, requestBody, error, status, responseBody) {
 			console.log('Request: ' + method + ' ' + url + ' body=' + JSON.stringify(requestBody));

src/6_branch.js

@@ -1340,19 +1340,22 @@ Branch.prototype['qrCode'] = wrap(
 		this._api(
 			resources.qrCode,
 			utils.cleanLinkData(linkData),
-			function(error, rawBuffer) {
-				function QrCode() { }
-				if (!error) {
-					QrCode['rawBuffer'] = rawBuffer;
-					QrCode['base64'] = function() {
-						// First Encode array buffer as UTF-8 String, then Base64 Encode
-						if (this['rawBuffer']) {
-							return btoa(String.fromCharCode.apply(null, new Uint8Array(this['rawBuffer'])));
-						}
-						throw Error('QrCode.rawBuffer is empty.');
-					};
-				}
-				return done(error || null, QrCode || null);
+			(error, rawBuffer) => {
+				if (error) return done(error, null);
+
+				const QrCode = {
+					rawBuffer,
+					base64() {
+						if (!this.rawBuffer) throw new Error('QrCode.rawBuffer is empty.');
+						// Encode the Uint8Array to a binary string, then convert to base64
+						const binaryString = Array.from(new Uint8Array(this.rawBuffer))
+							.map(byte => String.fromCharCode(byte))
+							.join('');
+						return btoa(binaryString);
+					}
+				};
+
+				return done(null, QrCode);
 			}
 		);
 	}