appengine: throw AssetErrors directly (instead of via new Future.error

lib/src/server/assets.dart

Index: lib/src/server/assets.dart
diff --git a/lib/src/server/assets.dart b/lib/src/server/assets.dart
index caf582936141cbfcfd805cc78fecf520ddb36033..04f251a61d44ab72620fa9b9c0c04358d93d1beb 100644
--- a/lib/src/server/assets.dart
+++ b/lib/src/server/assets.dart
@@ -48,9 +48,8 @@ class AssetsManager {
         })
         .catchError((e) {
           print("Unable to connect to 'pub serve' for '${request.uri}': $e");

[kevmoo, 2014/11/10 21:57:56]

Should we get rid of this print statement, too? Or move it to logging?

[kustermann, 2014/11/11 09:53:13]

"stdout" is currently our log for locally testing. Log messages here might not
be written with the logging service because the request is already done (see the
.pipe() above).

It's a nasty artifiact, that we can fix once we switch to the new way of doing
logging.

Please add a TODO here to use the logging service.

[kevmoo, 2014/11/11 15:15:52]

Done.

-          var error = new AssetError(
+          throw new AssetError(
               "Unable to connect to 'pub serve' for '${request.uri}': $e");
-          return new Future.error(error);
         });
   }
 
@@ -74,10 +73,9 @@ class AssetsManager {
           if (response.statusCode == HttpStatus.OK) {
             return response;
           } else {
-            var error = new AssetError(
+            throw new AssetError(
                 "Failed to fetch asset '$path' from pub: "
                 "${response.statusCode}.");
-            return new Future.error(error);
           }
         })
         .catchError((error) {
@@ -85,7 +83,7 @@ class AssetsManager {
             error = new AssetError(
                 "Failed to fetch asset '$path' from pub: '${path}': $error");
           }
-          return new Future.error(error);
+          throw error;
         });
   }
 
@@ -95,8 +93,7 @@ class AssetsManager {
       if (exists) {
         return new File(root + path).openRead();
       } else {
-        var error = new AssetError("Asset '$path' not found");
-        return new Future.error(error);
+        throw new AssetError("Asset '$path' not found");
       }
     });
   }