test events: added optional value type to extra event key/val pairs

The test events had worker indexes coming across as strings.  I
want them to be ints.  worker_index now comes across as an int in
the dicationary.

The optional type can be specified with:
--event-add-entries key=val[:type][,key2=val2[:type2]...]
The type piece may be 'int' at this time.  That is all.  Otherwise
it will be a string.

llvm-svn: 248066
diff --git a/lldb/test/dotest_args.py b/lldb/test/dotest_args.py
index 87213c5..481cd64 100644
--- a/lldb/test/dotest_args.py
+++ b/lldb/test/dotest_args.py
@@ -181,7 +181,9 @@
         '--event-add-entries',
         action='store',
         help=('Specify comma-separated KEY=VAL entries to add key and value '
-              'pairs to all test events generated by this test run.'))
+              'pairs to all test events generated by this test run.  VAL may '
+              'be specified as VAL:TYPE, where TYPE may be int to convert '
+              'the value to an int'))
     # Remove the reference to our helper function
     del X