Treat IPv6 link local addresses as loopback addresses.

net/base/net_util.cc

Index: net/base/net_util.cc
diff --git a/net/base/net_util.cc b/net/base/net_util.cc
index 4dd357fbc90e625c2341dace10504c034e968641..21c150c7d252b2b165a1c22f41a4c102f4aecadd 100644
--- a/net/base/net_util.cc
+++ b/net/base/net_util.cc
@@ -1831,6 +1831,14 @@ bool HaveOnlyLoopbackAddresses() {
     const struct sockaddr* addr = interface->ifa_addr;
     if (!addr)
       continue;
+    if (addr->sa_family == AF_INET6) {
+      // Safe cast since this is AF_INET6.
+      const struct sockaddr_in6* addr_in6 =
+          reinterpret_cast<const struct sockaddr_in6*>(addr);
+      const struct in6_addr* sin6_addr = &addr_in6->sin6_addr;
+      if (IN6_IS_ADDR_LOOPBACK(sin6_addr) || IN6_IS_ADDR_LINKLOCAL(sin6_addr))
+        continue;
+    }
     if (addr->sa_family != AF_INET6 && addr->sa_family != AF_INET)
       continue;