Set serial connection parameters immediately on connect.

device/serial/serial_io_handler.h

Index: device/serial/serial_io_handler.h
diff --git a/device/serial/serial_io_handler.h b/device/serial/serial_io_handler.h
index 46e0ed0fa2be1efd29b34935617ada01426c4a05..5f93d63270b0ffcc8f4a31db94d21054a90a1a2c 100644
--- a/device/serial/serial_io_handler.h
+++ b/device/serial/serial_io_handler.h
@@ -31,6 +31,7 @@ class SerialIoHandler : public base::NonThreadSafe,
 
   // Initiates an asynchronous Open of the device.
   virtual void Open(const std::string& port,
+                    const serial::ConnectionOptions& options,
                     const OpenCompleteCallback& callback);
 
   // Signals that the access request for |port| is complete.
@@ -74,7 +75,7 @@ class SerialIoHandler : public base::NonThreadSafe,
 
   // Performs platform-specific port configuration. Returns |true| iff
   // configuration was successful.
-  virtual bool ConfigurePort(const serial::ConnectionOptions& options) = 0;
+  bool ConfigurePort(const serial::ConnectionOptions& options);
 
   // Performs a platform-specific port configuration query. Fills values in an
   // existing ConnectionInfo. Returns |true| iff port configuration was
@@ -107,6 +108,9 @@ class SerialIoHandler : public base::NonThreadSafe,
   // Platform-specific write cancelation.
   virtual void CancelWriteImpl() = 0;
 
+  // Platform-specific port configuration applies options_ to the device.
+  virtual bool ConfigurePortImpl() = 0;
+
   // Requests access to the underlying serial device, if needed.
   virtual void RequestAccess(
       const std::string& port,
@@ -164,12 +168,16 @@ class SerialIoHandler : public base::NonThreadSafe,
 
   bool write_canceled() const { return write_canceled_; }
 
+  const serial::ConnectionOptions& options() const { return options_; }
+
   // Possibly fixes up a serial port path name in a platform-specific manner.
   static std::string MaybeFixUpPortName(const std::string& port_name);
 
  private:
   friend class base::RefCounted<SerialIoHandler>;
 
+  void MergeConnectionOptions(const serial::ConnectionOptions& options);
+
   // Continues an Open operation on the FILE thread.
   void StartOpen(const std::string& port,
                  scoped_refptr<base::MessageLoopProxy> io_message_loop);
@@ -186,6 +194,9 @@ class SerialIoHandler : public base::NonThreadSafe,
   // thread.
   base::File file_;
 
+  // Currently applied connection options.
+  serial::ConnectionOptions options_;
+
   scoped_ptr<WritableBuffer> pending_read_buffer_;
   serial::ReceiveError read_cancel_reason_;
   bool read_canceled_;