Fix a jdwp assert.

(From https://android-git.corp.google.com/g/161010.)

Change-Id: I8d9cd2cd526c4ced5db412ce2a1fa61f921c48de
diff --git a/src/jdwp/jdwp_main.cc b/src/jdwp/jdwp_main.cc
index 22767ef..72aff5c 100644
--- a/src/jdwp/jdwp_main.cc
+++ b/src/jdwp/jdwp_main.cc
@@ -429,7 +429,7 @@
 
   /* now get the current time */
   int64_t now = MilliTime();
-  CHECK_GT(now, last);
+  CHECK_GE(now, last);
 
   VLOG(jdwp) << "+++ debugger interval=" << (now - last);
   return now - last;