hg: jdk/submit: 8231630: Optimize boot loader with no bootclasspath append entry.

[jianglizhou at google.com]

Changeset: 0456f5d46244
Author:    jiangli
Date:      2019-10-05 13:13 -0700
URL:       https://hg.openjdk.java.net/jdk/submit/rev/0456f5d46244

8231630: Optimize boot loader with no bootclasspath append entry.
Summary: Optimize SystemDictionary::load_instance_class for boot loader. Immediately return NULL if the requested class is either in the unnamed package or unnamed module, or in a module not defined to the boot loader, when there is no bootclasspath append entry.
Reviewed-by: shade

! src/hotspot/share/classfile/classLoader.hpp
! src/hotspot/share/classfile/systemDictionary.cpp