Fix warnings in libusb.h so that other chromium code doesn't suffer.

third_party/libusb/windows-build.patch

+diff --git a/libusb/libusb.h b/libusb/libusb.h
+index de2d050..beff229 100644
+--- a/libusb/libusb.h
++++ b/libusb/libusb.h
+@@ -833,6 +833,10 @@ typedef void (LIBUSB_CALL *libusb_transfer_cb_fn)(struct libusb_transfer *transf
+  * completed, the library populates the transfer with the results and passes
+  * it back to the user.
+  */
++#if defined(OS_WIN)
++#pragma warning(push)
++#pragma warning(disable:4200)
++#endif  // defined(OS_WIN)
+ struct libusb_transfer {
+        /** Handle of the device that this transfer will be submitted to */
+        libusb_device_handle *dev_handle;
+@@ -884,12 +888,15 @@ struct libusb_transfer {
+        /** Isochronous packet descriptors, for isochronous transfers only. */
+        struct libusb_iso_packet_descriptor iso_packet_desc
+ #if defined(__STDC_VERSION__) && (__STDC_VERSION__ >= 199901L)
+-       [] /* valid C99 code */
++       [] /* valid C99 code */
+ #else
+-       [0] /* non-standard, but usually working code */
++       [0] /* non-standard, but usually working code */
+ #endif
+-       ;
++       ;
+ };
++#if defined(OS_WIN)
++#pragma warning(pop)
++#endif  // defined(OS_WIN)
+ 
+ /** \ingroup misc
+  * Capabilities supported by this instance of libusb. Test if the running
 diff --git a/libusb/os/poll_windows.h b/libusb/os/poll_windows.h
-index fee89f5..27986b8 100644
+index fee89f5..76bab0f 100644
 --- a/libusb/os/poll_windows.h
 +++ b/libusb/os/poll_windows.h
 @@ -19,6 +19,9 @@
   * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
   *
   */
 +
 +#ifndef LIBUSB_POLL_WINDOWS_H
 +#define LIBUSB_POLL_WINDOWS_H
  #pragma once
  
  #if defined(_MSC_VER)
-@@ -57,12 +60,6 @@ extern enum windows_version windows_version;
- #define POLLHUP     0x0010    /* Hung up */
- #define POLLNVAL    0x0020    /* Invalid request: fd not open */
+@@ -50,19 +53,6 @@ extern enum windows_version windows_version;
  
+ #define MAX_FDS     256
+ 
+-#define POLLIN      0x0001    /* There is data to read */
+-#define POLLPRI     0x0002    /* There is urgent data to read */
+-#define POLLOUT     0x0004    /* Writing now will not block */
+-#define POLLERR     0x0008    /* Error condition */
+-#define POLLHUP     0x0010    /* Hung up */
+-#define POLLNVAL    0x0020    /* Invalid request: fd not open */
+-
 -struct pollfd {
 -    int fd;           /* file descriptor */
 -    short events;     /* requested events */
 -    short revents;    /* returned events */
 -};
 -
  // access modes
  enum rw_type {
         RW_NONE,
-@@ -118,3 +115,4 @@ do {                                                    \
+@@ -118,3 +108,4 @@ do {                                                    \
  } while (0)
  #endif
  
 +#endif /* LIBUSB_POLL_WINDOWS_H */
 diff --git a/libusb/os/windows_usb.h b/libusb/os/windows_usb.h
 index b629d18..6dbfaf5 100644
 --- a/libusb/os/windows_usb.h
 +++ b/libusb/os/windows_usb.h
 @@ -101,8 +101,6 @@ const GUID GUID_DEVINTERFACE_USB_DEVICE = { 0xA5DCBF10, 0x6530, 0x11D2, {0x90, 0
  #if !defined(GUID_DEVINTERFACE_USB_HUB)
  const GUID GUID_DEVINTERFACE_USB_HUB = { 0xF18A0E88, 0xC30C, 0x11D0, {0x88, 0x15, 0x00, 0xA0, 0xC9, 0x06, 0xBE, 0xD8} };
  #endif
 -const GUID GUID_NULL = { 0x00000000, 0x0000, 0x0000, {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00} };
 -
  
  /*
   * Multiple USB API backend support
 diff --git a/msvc/config.h b/msvc/config.h
 index 43b4d4e..9ac6134 100644
 --- a/msvc/config.h
 +++ b/msvc/config.h
 @@ -19,3 +19,5 @@
  
  /* type of second poll() argument */
  #define POLL_NFDS_TYPE unsigned int
 +
 +#include <Winsock2.h>