I like the refactoring. Some more nits below. Please feel free to submit after fixing them. LGTM
http://gwt-code-reviews.appspot.com/674804/diff/9001/10002 File user/src/com/google/gwt/requestfactory/client/impl/RequestFactoryJsonImpl.java (right): http://gwt-code-reviews.appspot.com/674804/diff/9001/10002#newcode96 user/src/com/google/gwt/requestfactory/client/impl/RequestFactoryJsonImpl.java:96: // TODO: do something better here... This will probably not work. The client code cannot depend on the server code. Define the constant in RequestFactory? http://gwt-code-reviews.appspot.com/674804/diff/9001/10005 File user/src/com/google/gwt/user/server/rpc/RPCServletUtils.java (right): http://gwt-code-reviews.appspot.com/674804/diff/9001/10005#newcode377 user/src/com/google/gwt/user/server/rpc/RPCServletUtils.java:377: if (contentType.startsWith(expectedContentType)) { .toLowerCase() missing? http://gwt-code-reviews.appspot.com/674804/diff/9001/10006 File user/test/com/google/gwt/user/server/rpc/RPCServletUtilsTest.java (right): http://gwt-code-reviews.appspot.com/674804/diff/9001/10006#newcode293 user/test/com/google/gwt/user/server/rpc/RPCServletUtilsTest.java:293: return RPCServletUtils.readContentAsGwtRpc(m); Double-check? Translation seems different from line 181. http://gwt-code-reviews.appspot.com/674804/show -- http://groups.google.com/group/Google-Web-Toolkit-Contributors
