8228388: Add information about dirty/skipped card for Merge HCC in G1 log
Summary: Collect and print informatio about the number of processed cards during the Merge HCC phase to improve log output.
Reviewed-by: kbarrett, sangheki
Welcome to the JDK!
===================
For information about building the JDK, including how to retrieve all
of the source code, please see either of these files:
* doc/building.html (html version)
* doc/building.md (markdown version)
See http://openjdk.java.net/ for more information about the OpenJDK
Community and the JDK.