Ensure serialVersionUID computation for Throwable subclass is stable

Adds a test to ensure that the default serialVersionUID computed for
a Throwable subclass in an app with targetSdkVersion=23 does not change.
This is to protect against changes in Throwable breaking existing
behavior in those apps.

Did not add a test to check the default SUID computed for a Throwable
subclass for apps with targetSdkVersion>=23 as that behavior is
well tested in
    ./luni/src/test/java/libcore/java/io/ObjectStreamClassTest.java

(cherry picked 24ac60ad50fd9b984dd5de68c64c2acc9ee0823a)

Bug: 109930347
Test: atest core-tests:libcore.java.lang.ThrowableTest
Change-Id: I0d53d935919f1dcb2cc2cd082fc0dd4e6f1e86ce
1 file changed