Refine PNaCl pexe fetch UMA errors to know if the user aborted, etc.

ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc

Index: ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc
diff --git a/ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc b/ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc
index bd551ebcc7c7f1772430d398460a97ae8181f571..5bc43f1291cfe690389fd4f3ab91beb07d1f4f50 100644
--- a/ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc
+++ b/ppapi/native_client/src/trusted/plugin/pnacl_translate_thread.cc
@@ -200,7 +200,7 @@ void PnaclTranslateThread::DoTranslate() {
     PLUGIN_PRINTF(("PnaclTranslateThread StreamEnd failed\n"));
     if (llc_subprocess_->srpc_client()->GetLastError() ==
         NACL_SRPC_RESULT_APP_ERROR) {
-      // The error string is only present if the error was sent back from llc
+      // The error string is only present if the error was sent back from llc.
       TranslateFailed(ERROR_PNACL_LLC_INTERNAL,
                       params.outs()[3]->arrays.str);
     } else {