Fixed a bunch of errors reported after specifying -stdlib=libc++.
Made protubuf-plugin-closure Makefile link against libc++.
Updated gtest-1.6.0 to trunk.
Made the gtest makefile possibly have all our QUIET changes and the like, properly, again.
Turned off missing-field-initializers warning in gtest.
Merge branch 'next' into sam_libcxx
Added $(QUIET) to rm line in gtest makefile.
Merge branch 'sam_libcxx' into sam_no_ptr_bag