Default TimeZone is GMT not local if user.timezone is invalid on Mac OS

FULL PRODUCT VERSION :
java version "1.7.0_60"
Java(TM) SE Runtime Environment (build 1.7.0_60-b19)
Java HotSpot(TM) 64-Bit Server VM (build 24.60-b09, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Darwin My-MacBook-Pro.local 13.4.0 Darwin Kernel Version 13.4.0: Sun Aug 17 19:50:11 PDT 2014; root:xnu-2422.115.4~1/RELEASE_X86_64 x86_64

EXTRA RELEVANT SYSTEM CONFIGURATION :
Timezone is America/New_York

A DESCRIPTION OF THE PROBLEM :
When the system property user.timezone is set to an invalid timezone (e.g. "foo/bar"), the timezone returned by TimeZone.getDefault() is always GMT. The timezone has the correct default when user.timezone is not set. After getting the default timezone, the user.timezone property is set to "GMT}05:00" where } is an unprintable character. This also affects creating a new Date object.

I don't know where to put it, but, if you look at:
http://hg.openjdk.java.net/jdk7u/jdk7u/jdk/file/5cca2f1a37da/src/solaris/native/java/util/TimeZone_md.c#l690
and:
http://hg.openjdk.java.net/jdk7u/jdk7u/jdk/file/5cca2f1a37da/src/solaris/native/java/util/TimeZone_md.c#l693

It sets a char to a string literal. This does not exist in the jdk7 source. It does exist in jdk8 and jdk8u

ADDITIONAL REGRESSION INFORMATION:
This commit introduced the bug to jdk7u: http://hg.openjdk.java.net/jdk7u/jdk7u/jdk/rev/5cca2f1a37da

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Run the attached code with:
java -Duser.timezone=foo/bar JavaTest

The expected behavior was calculated by running:
java -Duser.timezone=GMT-05:00 JavaTest

Note: in iTerm2 the } in the actual result renders as �

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
u.t: GMT-05:00
a date: Tue Dec 02 13:31:19 GMT-05:00 2014
timezone: sun.util.calendar.ZoneInfo[id="GMT-05:00",offset=-18000000,dstSavings=0,useDaylight=false,transitions=0,lastRule=null]
u.t: GMT-05:00
ACTUAL -
u.t: foo/bar
a date: Tue Dec 02 18:15:11 GMT 2014
timezone: sun.util.calendar.ZoneInfo[id="GMT",offset=0,dstSavings=0,useDaylight=false,transitions=0,lastRule=null]
u.t: GMT}05:00

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.util.*;

public class JavaTest {
    public static void main(String[] args) throws Exception {

        System.out.println("u.t: " + System.getProperty("user.timezone"));
        System.out.println("a date: " + new Date());
        System.out.println("timezone: " + TimeZone.getDefault());
        System.out.println("u.t: " + System.getProperty("user.timezone"));
    }
}

---------- END SOURCE ----------