Integrate luni module (but not tests) to Harmony r772995.

Integrate luni module (but not tests) to Harmony r772995.

Notable changes
     - Stripped "@since Android 1.0" from many files. Most files
       are now 100% the same in Dalvik and Harmony.
     - AbstractStringBuilder.reverse() supports surrogates
     - AbstractStringBuilder shares less to waste less memory
     - Bitset optimized
     - BufferedInputStream changed to support unsynchronized close()
     - BufferedOutputStream does flushInternal
     - BufferedReader supports EBCDIC NEL
     - Collections.synchronizedList().indexOf() does a copy for more concurrency
     - Classes in nio module changed: DatagramChannelImpl, SocketChannelImpl
       and ServerSocketChannelImpl (these depend on internal APIs changed in
       this update)
     - DataInputStream/DataOutputStream now use a small buffer to limit the
       number of times the underlying stream is accessed
     - Date now has a minutes offset, more efficient toString()
     - ExposedByteArrayInputStream: new internal class
     - DeleteOnExit moved to top-level class
     - FileDescriptor.isValid() now non-native
     - Float, Double lessThan optimized (fix for compare(-0.0F, 0.0F) still pending)
     - FileURLConnection now guesses content types from streams
     - HashMap iterator changes
     - Hashtable iterator changes
     - INetworkSystem
       - removes bind2(), createMulticastSocket, sendStream(),
       - renames createSocket to createStreamSocket
     - JarURLConnection rewritten
     - LinkedHashMap: new iterator
     - Locale, Currency, TimeZone: now use ICU in Harmony, plain Java in Dalvik
     - ObjectInputStream: Accessor objects in Harmony, direct native in Dalvik
     - ProxyClassFile - many changes
     - String - optimized ascii for toLowerCase, toUpperCase, compare
     - Timer - rewritten
     - TreeMap - rewritten
     - URLClassLoader - new
     - URLConnection - new guessContentTypeFromStream(), uses org.apache.harmony.awt.www.content
       to lookup content type handlers