clang-format: Don't wrap after @interface.

This fixes llvm.org/PR19450.

Before:
  @interface
  BookmarkHomeHandsetViewController ()<BookmarkAllCollectionViewDelegate,
                                       BookmarkFolderCollectionViewDelegate,
                                       BookmarkMenuViewControllerDelegate,
                                       BookmarkSearchViewControllerDelegate> {
  }

After:
  @interface aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa ()<
      aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,
      aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,
      aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa,
      aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa> {
  }

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@207400 91177308-0d34-0410-b5e6-96231b3b80d8