Network details: nameservers: stop learn more propagation

TBR=stevenjb@chromium.org

(cherry picked from commit 35328cc5ac8aafaefff8a50077074374ff5a77a0)

Bug: 810328
Change-Id: I511732bfc5429c58477b09a33fb8d83f3ba10539
Reviewed-on: https://chromium-review.googlesource.com/914925
Reviewed-by: Toni Barzic <tbarzic@chromium.org>
Commit-Queue: Steven Bennetts <stevenjb@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#536472}
Reviewed-on: https://chromium-review.googlesource.com/929582
Reviewed-by: Steven Bennetts <stevenjb@chromium.org>
Cr-Commit-Position: refs/branch-heads/3325@{#539}
Cr-Branched-From: bc084a8b5afa3744a74927344e304c02ae54189f-refs/heads/master@{#530369}
diff --git a/ui/webui/resources/cr_components/chromeos/network/network_nameservers.html b/ui/webui/resources/cr_components/chromeos/network/network_nameservers.html
index 7cf53ba..0f8bc18 100644
--- a/ui/webui/resources/cr_components/chromeos/network/network_nameservers.html
+++ b/ui/webui/resources/cr_components/chromeos/network/network_nameservers.html
@@ -69,7 +69,7 @@
           <template is="dom-if"
               if="[[i18nExists('networkGoogleNameserversLearnMoreUrl')]]">
             <a href="[[i18n('networkGoogleNameserversLearnMoreUrl')]]"
-                target="_blank">
+                target="_blank" on-tap="doNothing_">
               [[i18n('networkNameserversLearnMore')]]
             </a>
           </template>
diff --git a/ui/webui/resources/cr_components/chromeos/network/network_nameservers.js b/ui/webui/resources/cr_components/chromeos/network/network_nameservers.js
index b9e9cf4..c59320d 100644
--- a/ui/webui/resources/cr_components/chromeos/network/network_nameservers.js
+++ b/ui/webui/resources/cr_components/chromeos/network/network_nameservers.js
@@ -238,4 +238,12 @@
   clearEmptyNameServers_: function(nameservers) {
     return nameservers.filter((nameserver) => !!nameserver);
   },
+
+  /**
+   * @param {!Event} event
+   * @private
+   */
+  doNothing_: function(event) {
+    event.stopPropagation();
+  },
 });