Switch Pepper Linux to use shared USB<->native key conversion table.

ui/base/keycodes/usb_keycode_map.h

 // Copyright (c) 2012 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.
 
 // Data in this file was created by referencing:
 //  USB HID Usage Tables (v1.11) 27 June 2001
 //  HIToolbox/Events.h (Mac)
 
 #include <stdint.h>
 
@@ skipping 358 matching lines @@
   USB_KEYMAP(0x0c0224, 0x00a6, 0xe06a, 0xffff),  // AC_Back
   USB_KEYMAP(0x0c0225, 0x00a7, 0xe069, 0xffff),  // AC_Forward
   USB_KEYMAP(0x0c0226, 0x0000, 0xe068, 0xffff),  // AC_Stop
   USB_KEYMAP(0x0c0227, 0x00b5, 0xe067, 0xffff),  // AC_Refresh (Reload)
   USB_KEYMAP(0x0c022a, 0x00a4, 0xe066, 0xffff),  // AC_Bookmarks (Favorites)
   USB_KEYMAP(0x0c0289, 0x00f0, 0x0000, 0xffff),  // AC_Reply
   USB_KEYMAP(0x0c028b, 0x00f1, 0x0000, 0xffff),  // AC_ForwardMsg (MailForward)
   USB_KEYMAP(0x0c028c, 0x00ef, 0x0000, 0xffff),  // AC_Send
 };
 
-const uint16_t kInvalidKeycode = usb_keycode_map[0].native_keycode;
+inline uint16_t InvalidNativeKeycode() {
+  return usb_keycode_map[0].native_keycode;
+}
 
-static uint16 UsbKeycodeToNativeKeycode(uint32_t usb_keycode) {
+inline uint16_t InvalidUsbKeycode() {
+  return usb_keycode_map[0].usb_keycode;
+}
+
+inline uint16_t UsbKeycodeToNativeKeycode(uint32_t usb_keycode) {
   // Deal with some special-cases that don't fit the 1:1 mapping.
   if (usb_keycode == 0x070032) // non-US hash.
     usb_keycode = 0x070031; // US backslash.
 #if defined(OS_MACOSX)
   if (usb_keycode == 0x070046) // PrintScreen.
     usb_keycode = 0x070068; // F13.
 #endif
 
   for (size_t i = 0; i < arraysize(usb_keycode_map); ++i) {
     if (usb_keycode_map[i].usb_keycode == usb_keycode)
       return usb_keycode_map[i].native_keycode;
   }
-  return kInvalidKeycode;
+  return InvalidNativeKeycode();
 }
+
+inline uint32_t NativeKeycodeToUsbKeycode(uint16_t native_keycode) {
+  for (size_t i = 0; i < arraysize(usb_keycode_map); ++i) {
+    if (usb_keycode_map[i].native_keycode == native_keycode)
+      return usb_keycode_map[i].usb_keycode;
+  }
+  return InvalidUsbKeycode();
+}