go: update go build rules

examples/go/echo_server.go

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package main
 
 import (
         "log"
 
         "code.google.com/p/go.mobile/app"
 
         "mojo/public/go/application"
         "mojo/public/go/bindings"
         "mojo/public/go/system"
 
         "examples/echo/echo"
 )
 
 //#include "mojo/public/c/system/types.h"
 import "C"
 
 type EchoImpl struct{}
 
 func (echo *EchoImpl) EchoString(inValue *string) (outValue *string, err error) {
-        log.Println(*inValue)
+        log.Printf("server: %s\n", *inValue)
         return inValue, nil
 }
 
 type EchoServerDelegate struct {
         stubs []*bindings.Stub
 }
 
 func (delegate *EchoServerDelegate) Initialize(context application.Context) {}
 
 func (delegate *EchoServerDelegate) Create(request echo.EchoRequest) {
@@ skipping 22 matching lines @@
 
 //export MojoMain
 func MojoMain(handle C.MojoHandle) C.MojoResult {
         application.Run(&EchoServerDelegate{}, system.MojoHandle(handle))
         return C.MOJO_RESULT_OK
 }
 
 func main() {
         app.Run(app.Callbacks{})
 }