Added a message that suggest to configure a proxy for a network.

chrome/browser/resources/chromeos/login/oobe.css

Index: chrome/browser/resources/chromeos/login/oobe.css
diff --git a/chrome/browser/resources/chromeos/login/oobe.css b/chrome/browser/resources/chromeos/login/oobe.css
index 3eabcb53e90a160e2f84cd11adb0dd0ce30657c5..bccb66fb781b72fd1c5337c3c9129d09618718dc 100644
--- a/chrome/browser/resources/chromeos/login/oobe.css
+++ b/chrome/browser/resources/chromeos/login/oobe.css
@@ -98,6 +98,7 @@ hr.bottom {
 #header span,
 #user-image-screen-curtain p,
 .label,
+.flexible-label,
 .menu-control {
   cursor: default;
 }
@@ -224,13 +225,21 @@ html[dir=rtl]  .step.left {
   width: 250px;
 }
 
-.label {
+.label,
+.flexible-label {
   display: block;
   margin: 5px 5px 5px 0;
   padding: 5px 5px 5px 0;
+}
+
+.label {
   width: 170px;
 }
 
+.flexible-label {
+  max-width: 250px;
+}
+
 #connect {
   box-sizing: border-box;
   padding: 60px 0 0 145px;