pull in v11.0.1 from upstream

resources/js/lib/Lazy.js

@@ -0,0 +1,33 @@
+export default function LazyLoadInit()
+{
+  document.addEventListener('DOMContentLoaded', LazyLoad());
+}
+
+function LazyLoad() {
+
+  var lazyImages = [].slice.call(document.querySelectorAll('img.lazy'));
+
+  if ('IntersectionObserver' in window) {
+    let lazyImageObserver = new IntersectionObserver(function(entries, observer) {
+      entries.forEach(function(entry) {
+        if (entry.isIntersecting) {
+          let lazyImage = entry.target;
+          lazyImage.src = lazyImage.dataset.src;
+
+          if(lazyImage.dataset.srcset) {
+            lazyImage.srcset = lazyImage.dataset.srcset;
+          }
+
+          lazyImage.classList.remove('lazy');
+          lazyImageObserver.unobserve(lazyImage);
+        }
+      });
+    });
+
+    lazyImages.forEach(function(lazyImage) {
+      lazyImageObserver.observe(lazyImage);
+    });
+  } else {
+    // Possibly fall back to a more compatible method here
+  }
+}