Throw a more tailored error when a storage upgrade patch can't access a database

Summary: Fixes T8762.

Test Plan: Ran `bin/storage upgrade --namespace ... --user limited`, saw a more specific error.

Reviewers: chad

Reviewed By: chad

Maniphest Tasks: T8762

Differential Revision: https://secure.phabricator.com/D15080

src/infrastructure/storage/management/PhabricatorStorageManagementAPI.php

@@ -256,10 +256,19 @@ final class PhabricatorStorageManagementAPI extends Phobject {
         $query = str_replace('{$'.$key.'}', $value, $query);
       }
 
-      queryfx(
-        $conn,
-        '%Q',
-        $query);
+      try {
+        queryfx($conn, '%Q', $query);
+      } catch (AphrontAccessDeniedQueryException $ex) {
+        throw new PhutilProxyException(
+          pht(
+            'Unable to access a required database or table. This almost '.
+            'always means that the user you are connecting with ("%s") does '.
+            'not have sufficient permissions granted in MySQL. You can '.
+            'use `bin/storage databases` to get a list of all databases '.
+            'permission is required on.',
+            $this->getUser()),
+          $ex);
+      }
     }
   }