Fix socket usage in forwarder2.

tools/android/forwarder2/socket.h

Index: tools/android/forwarder2/socket.h
diff --git a/tools/android/forwarder2/socket.h b/tools/android/forwarder2/socket.h
index b86fd9e7aa67a3e997a04f0d63e8079e11deeb74..33d72fcfedc030eb3fdf13a53918072e8c7704dd 100644
--- a/tools/android/forwarder2/socket.h
+++ b/tools/android/forwarder2/socket.h
@@ -50,9 +50,17 @@ class Socket {
   // Returns the number of bytes read.
   int Read(void* buffer, size_t buffer_size);
 
-  // Same as Read(), just a wrapper around write().
+  // Non-blocking version of Read() above. This must be called after a
+  // successful call to select(). The socket must also be in non-blocking mode
+  // before calling this method.
+  int NonBlockingRead(void* buffer, size_t buffer_size);
+
+  // Wrapper around send().
   int Write(const void* buffer, size_t count);
 
+  // Same as NonBlockingRead() but for writing.
+  int NonBlockingWrite(const void* buffer, size_t count);
+
   // Calls Read() multiple times until num_bytes is written to the provided
   // buffer. No bounds checking is performed.
   // Returns number of bytes read, which can be different from num_bytes in case
@@ -105,6 +113,8 @@ class Socket {
     bool was_fired;
   };
 
+  bool SetNonBlocking();
+
   // If |host| is empty, use localhost.
   bool InitTcpSocket(const std::string& host, int port);
   bool InitUnixSocket(const std::string& path);