Fixed: Show correct error on unauthorized caps call

(cherry picked from commit f2b0fc946e1fb1b4649f1b46a003bd2add09a461)

src/NzbDrone.Core/Indexers/Newznab/NewznabCapabilitiesProvider.cs

@@ -7,6 +7,7 @@ using NzbDrone.Common.Cache;
 using NzbDrone.Common.Extensions;
 using NzbDrone.Common.Http;
 using NzbDrone.Common.Serializer;
+using NzbDrone.Core.Indexers.Exceptions;
 
 namespace NzbDrone.Core.Indexers.Newznab
 {
@@ -73,6 +74,13 @@ namespace NzbDrone.Core.Indexers.Newznab
                 _logger.Debug(ex, "Failed to parse newznab api capabilities for {0}", indexerSettings.BaseUrl);
                 throw;
             }
+            catch (ApiKeyException ex)
+            {
+                ex.WithData(response, 128 * 1024);
+                _logger.Trace("Unexpected Response content ({0} bytes): {1}", response.ResponseData.Length, response.Content);
+                _logger.Debug(ex, "Failed to parse newznab api capabilities for {0}, invalid API key", indexerSettings.BaseUrl);
+                throw;
+            }
             catch (Exception ex)
             {
                 ex.WithData(response, 128 * 1024);