[Smart Lock] Add a generic error message for out-of-date software.

This message is shown when the remote device's name cannot be determined.

BUG=453998
TEST=none
R=tengs@chromium.org

Review URL: https://codereview.chromium.org/1008263003

Cr-Commit-Position: refs/heads/master@{#321321}
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 5b8d67b5..923992c 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -15468,6 +15468,9 @@
       <message name="IDS_EASY_UNLOCK_SETUP_ERROR_REMOTE_SOFTWARE_OUT_OF_DATE" desc="The error message to display when the user's phone software is too old for compatibility with Easy Unlock. Note that the &lt;a&gt; element surrounds a link; these HTML elements should be preserved in the translation.">
         Found your <ph name="PHONE_TYPE">$1<ex>LGE Nexus 5</ex></ph>. But Smart Lock only works on devices with Android 5.0 and up. &lt;a&gt;Learn more&lt;/a&gt;
       </message>
+      <message name="IDS_EASY_UNLOCK_SETUP_ERROR_REMOTE_SOFTWARE_OUT_OF_DATE_GENERIC" desc="The generic error message to display when the user's phone software is too old for compatibility with Easy Unlock. This is only shown when the user's phone type is not known. Note that the &lt;a&gt; element surrounds a link; these HTML elements should be preserved in the translation.">
+        Found your phone. But Smart Lock only works on devices with Android 5.0 and up. &lt;a&gt;Learn more&lt;/a&gt;
+      </message>
       <message name="IDS_EASY_UNLOCK_SETUP_ERROR_FINDING_PHONE" desc="A generic catch-all error message to display when something goes wrong after the user clicks 'Find my phone' during Easy Unlock setup. Note that the &lt;a&gt; element surrounds a link; these HTML elements should be preserved in the translation.">
         Can’t find your phone. Make sure you’re using a compatible Android phone that’s turned on and within arm’s reach. &lt;a&gt;Learn more&lt;/a&gt;
       </message>
diff --git a/chrome/browser/extensions/api/easy_unlock_private/easy_unlock_private_api.cc b/chrome/browser/extensions/api/easy_unlock_private/easy_unlock_private_api.cc
index 066dede..52df0e34 100644
--- a/chrome/browser/extensions/api/easy_unlock_private/easy_unlock_private_api.cc
+++ b/chrome/browser/extensions/api/easy_unlock_private/easy_unlock_private_api.cc
@@ -313,6 +313,10 @@
       l10n_util::GetStringUTF16(
           IDS_EASY_UNLOCK_SETUP_ERROR_REMOTE_SOFTWARE_OUT_OF_DATE));
   strings->SetString(
+      "setupErrorRemoteSoftwareOutOfDateGeneric",
+      l10n_util::GetStringUTF16(
+          IDS_EASY_UNLOCK_SETUP_ERROR_REMOTE_SOFTWARE_OUT_OF_DATE_GENERIC));
+  strings->SetString(
       "setupErrorFindingPhone",
       l10n_util::GetStringUTF16(IDS_EASY_UNLOCK_SETUP_ERROR_FINDING_PHONE));
   strings->SetString(