Use event path to detect if anchor has been clicked in WebUIs.

ui/webui/resources/js/util.js

Index: ui/webui/resources/js/util.js
diff --git a/ui/webui/resources/js/util.js b/ui/webui/resources/js/util.js
index 293205804389a21425c26bc0c26756533d9e42ea..b3d3ba4cb54d21be325da581830b3e1af277c5da 100644
--- a/ui/webui/resources/js/util.js
+++ b/ui/webui/resources/js/util.js
@@ -216,26 +216,43 @@ document.addEventListener('click', function(e) {
   if (e.defaultPrevented)
     return;
 
+  var eventPath = e.path;
+  var anchor = null;
+  if (eventPath) {
+    for (var i = 0; i < eventPath.length; i++) {
+      var element = eventPath[i];
+      if (element.tagName === 'A' && element.href) {
+        anchor = element;
+        break;
+      }
+    }
+  }

[Dan Beam, 2016/08/08 19:29:48]

could this work?

/**
 * @param {!Node} node
 * @return {boolean} Whether |node| is an <a href>.
 */
function isAnchorWithHref(node) {
  return node.nodeName == 'A' && node.href;
}

var anchor = e.path ? e.path.find(isAnchorWithHref) :
    findAncestor(e.target, isAnchorWithHref);

[Dan Beam, 2016/08/08 21:28:00]

actually, Array#find might also suck wrt compat UGH

+
   var el = e.target;
-  if (el.nodeType == Node.ELEMENT_NODE &&
+  if (!anchor && el.nodeType == Node.ELEMENT_NODE &&
       el.webkitMatchesSelector('A, A *')) {
     while (el.tagName != 'A') {
       el = el.parentElement;
+      anchor = element;
+      break;
     }
+  }
 
-    if ((el.protocol == 'file:' || el.protocol == 'about:') &&
-        (e.button == 0 || e.button == 1)) {
-      chrome.send('navigateToUrl', [
-        el.href,
-        el.target,
-        e.button,
-        e.altKey,
-        e.ctrlKey,
-        e.metaKey,
-        e.shiftKey
-      ]);
-      e.preventDefault();
-    }
+  if (!anchor)
+    return;
+

[Dan Beam, 2016/08/08 19:29:47]

nit: anchor = /** @type {!HTMLAnchorElement} */(anchor);

[calamity, 2016/08/09 08:39:07]

Done.

+  if ((anchor.protocol == 'file:' || anchor.protocol == 'about:') &&
+      (e.button == 0 || e.button == 1)) {
+    chrome.send('navigateToUrl', [
+      anchor.href,
+      anchor.target,
+      e.button,
+      e.altKey,
+      e.ctrlKey,
+      e.metaKey,
+      e.shiftKey
+    ]);
+    e.preventDefault();
   }
 });