Clean up HID backend and API.

device/hid/hid_connection_linux.h

Index: device/hid/hid_connection_linux.h
diff --git a/device/hid/hid_connection_linux.h b/device/hid/hid_connection_linux.h
index 37d6cb08714ef7e488b6afaf0725d9bf14c77745..cee9bdbfde15a9956f77653acc6c6a5d9aac089b 100644
--- a/device/hid/hid_connection_linux.h
+++ b/device/hid/hid_connection_linux.h
@@ -11,7 +11,6 @@
 #include "device/hid/hid_connection.h"
 #include "device/hid/hid_device_info.h"
 #include "device/hid/hid_service_linux.h"
-#include "net/base/io_buffer.h"
 
 namespace device {
 
@@ -21,17 +20,13 @@ class HidConnectionLinux : public HidConnection,
   HidConnectionLinux(HidDeviceInfo device_info,
                      ScopedUdevDevicePtr udev_raw_device);
 
-  virtual void Read(scoped_refptr<net::IOBuffer> buffer,
-                    size_t size,
+  virtual void Read(scoped_refptr<net::IOBufferWithSize> buffer,
                     const IOCallback& callback) OVERRIDE;
-  virtual void Write(scoped_refptr<net::IOBuffer> buffer,
-                     size_t size,
+  virtual void Write(scoped_refptr<net::IOBufferWithSize> buffer,
                      const IOCallback& callback) OVERRIDE;
-  virtual void GetFeatureReport(scoped_refptr<net::IOBuffer> buffer,
-                                size_t size,
+  virtual void GetFeatureReport(scoped_refptr<net::IOBufferWithSize> buffer,
                                 const IOCallback& callback) OVERRIDE;
-  virtual void SendFeatureReport(scoped_refptr<net::IOBuffer> buffer,
-                                 size_t size,
+  virtual void SendFeatureReport(scoped_refptr<net::IOBufferWithSize> buffer,
                                  const IOCallback& callback) OVERRIDE;
 
   bool initialized() const { return initialized_; }
@@ -52,12 +47,8 @@ class HidConnectionLinux : public HidConnection,
   base::PlatformFile device_file_;
   base::MessagePumpLibevent::FileDescriptorWatcher device_file_watcher_;
 
-  typedef std::pair<scoped_refptr<net::IOBuffer>, size_t> PendingReport;
-  typedef Tuple3<scoped_refptr<net::IOBuffer>, size_t, IOCallback>
-      PendingRequest;
-
-  std::queue<PendingReport> input_reports_;
-  std::queue<PendingRequest> read_queue_;
+  std::queue<PendingHidReport> pending_reports_;
+  std::queue<PendingHidRead> pending_reads_;
 
   bool initialized_;