Send connection preface and setting when the okhttp client transport starts, this is required for talking to netty server.

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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=77104268

core/src/main/java/com/google/net/stubby/newtransport/okhttp/OkHttpClientTransport.java

@@ -149,6 +149,9 @@ public class OkHttpClientTransport extends AbstractClientTransport {
       Variant variant = new Http20Draft14();
       frameReader = variant.newReader(source, true);
       frameWriter = new AsyncFrameWriter(variant.newWriter(sink, true), this, executor);
+      frameWriter.connectionPreface();
+      Settings settings = new Settings();
+      frameWriter.settings(settings);
     }
 
     clientFrameHandler = new ClientFrameHandler();