Lazily throw pubspec parsing exceptions.

sdk/lib/_internal/pub/lib/src/command.dart

Index: sdk/lib/_internal/pub/lib/src/command.dart
diff --git a/sdk/lib/_internal/pub/lib/src/command.dart b/sdk/lib/_internal/pub/lib/src/command.dart
index 9689cc6e9e81e70be0933e63f025bfd71ab70f01..94ab4f890fd68a41944baea8ce076736de1e6517 100644
--- a/sdk/lib/_internal/pub/lib/src/command.dart
+++ b/sdk/lib/_internal/pub/lib/src/command.dart
@@ -128,17 +128,9 @@ and include the results in a bug report on http://dartbug.com/new.
       if (commandFuture == null) return true;
 
       return commandFuture;
-    }).whenComplete(() => cache.deleteTempDir()).catchError((e) {
-      if (e is PubspecNotFoundException && e.name == null) {
-        e = new ApplicationException('Could not find a file named '
-            '"pubspec.yaml" in the directory ${path.current}.');
-      } else if (e is PubspecHasNoNameException && e.name == null) {
-        e = new ApplicationException('pubspec.yaml is missing the required '
-            '"name" field (e.g. "name: ${path.basename(path.current)}").');
-      }
-
-      handleError(e);
-    }).then((_) {
+    }).whenComplete(() => cache.deleteTempDir())
+        .catchError(handleError)
+        .then((_) {
       // Explicitly exit on success to ensure that any dangling dart:io handles
       // don't cause the process to never terminate.
       exit(0);