vim-patch:7.4.1727

Problem:    Cannot detect a crash in tests when caused by garbagecollect().
Solution:   Add garbagecollect_for_testing().  Do not free a job if is still
            useful.

ebf7dfa6f1

src/nvim/eval.h

@@ -127,6 +127,7 @@ typedef enum {
     VV__NULL_LIST,  // List with NULL value. For test purposes only.
     VV__NULL_DICT,  // Dictionary with NULL value. For test purposes only.
     VV_VIM_DID_ENTER,
+    VV_TESTING,
     VV_TYPE_NUMBER,
     VV_TYPE_STRING,
     VV_TYPE_FUNC,