code: private void processAddDependency(Node n, Node parent) {
      CodingConvention convention = compiler.getCodingConvention();
      List<String> typeDecls =
          convention.identifyTypeDeclarationCall(n);
  
      // TODO(nnaze): Use of addDependency() should someday cause a warning
      // as we migrate users to explicit goog.forwardDeclare() calls.
      if (typeDecls != null) {
        for (String typeDecl : typeDecls) {
          compiler.forwardDeclareType(typeDecl);
        }
      }
  
      // We can't modify parent, so just create a node that will
      // get compiled out.
      Node emptyNode = IR.number(0);
      parent.replaceChild(n, emptyNode);
      compiler.reportChangeToEnclosingScope(emptyNode);
    }
docs: Process a goog.addDependency() call and record any forward declarations.