down integrate to svn


git-svn-id: http://protobuf.googlecode.com/svn/trunk@530 630680e5-0e50-0410-840e-4b1c322b438d
add printUnicode methods in TextFormat


git-svn-id: http://protobuf.googlecode.com/svn/trunk@531 630680e5-0e50-0410-840e-4b1c322b438d
delete unused variable


git-svn-id: http://protobuf.googlecode.com/svn/trunk@532 630680e5-0e50-0410-840e-4b1c322b438d
Add iostream in message.cc. Remove unused in coded_stream_unittest.cc


git-svn-id: http://protobuf.googlecode.com/svn/trunk@533 630680e5-0e50-0410-840e-4b1c322b438d