Request for review and approval to fix 8012366 in 7update

[Tim Bell]

All-

My fix for 8007815 [1] did not handle the case of an OpenJDK build that 
does not have the closed source trees.  If a user tries to build that 
far, the build will fail with "cd: can't cd to 
./install/make/installer/binaries/linux"

This is a request for review and approval to fix 8012366 in 7u. These 
changes will not throw a build error if the closed directories do not 
exist.  Makefile changes only; no product code has been modified:

Link to the bug report:

    http://bugs.sun.com/view_bug.do?bug_id=8012366

webrev of the Makefile changes:

   http://cr.openjdk.java.net/~tbell/8012366/webrev.00/

Thanks in advance-

Tim
[1]  There is no external link for 8007815, sorry.  These changes had to 
do with building and packaging in the install tree.