Revert 143656 - Add an IPC channel between the NaCl loader process and the renderer.
BUG=116317
TEST=ppapi, nacl tests, manual testing for experimental IPC proxy.
Review URL: https://chromiumcodereview.appspot.com/10641016

TBR=bbudge@chromium.org
Review URL: https://chromiumcodereview.appspot.com/10625007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@143665 0039d316-1c4b-4281-b951-d872f2087c98
  int32_t PrintBegin(const PP_PrintSettings_Dev& print_settings) {
    if (ppp_printing_ != NULL) {
      return ppp_printing_->Begin(plugin_->pp_instance(), &print_settings);
    }
    return 0;
  }

  int32_t PrintBegin(const PP_PrintSettings_Dev& print_settings) {
    if (ppp_printing_ != NULL) {
      return ppp_printing_->Begin(plugin_->pp_instance(), &print_settings);
    }
    return 0;
  }
