anchor.diff:    /**
      * Return `true` if the given [file] should be analyzed.
      */
  -  bool _shouldFileBeAnalyzed(File file) {
  +  bool _shouldFileBeAnalyzed(File file, {bool mustExist = true}) {
       for (Glob glob in analyzedFilesGlobs) {
         if (glob.matches(file.path)) {
           // Emacs creates dummy links to track the fact that a file is open for
  
positive.code:         // the non-existent file 'username@hostname.pid'. To avoid these dummy
          // links causing the analyzer to thrash, just ignore links to
          // non-existent files.
          return file.exists;
        }
      }
      return false;
  
negative.code:           }
          }
  
          Resource resource = resourceProvider.getResource(path);
          if (resource is File &&
              _shouldFileBeAnalyzed(resource, mustExist: false)) {
            callbacks.applyFileRemoved(info.analysisDriver, path);
          }
          break;
        case ChangeType.MODIFY:
          Resource resource = resourceProvider.getResource(path);
  