Issue #1595 part 5: Remove Vista checks in Windows widget code

widget/windows/KeyboardLayout.cpp

@@ -1016,9 +1016,7 @@ NativeKey::GetScanCodeWithExtendedFlag() const
   // MapVirtualKeyEx() has been improved for supporting extended keys since
   // Vista.  When we call it for mapping a scancode of an extended key and
   // a virtual keycode, we need to add 0xE000 to the scancode.
-  // On Win XP and Win Server 2003, this doesn't support. On them, we have
-  // no way to get virtual keycodes from scancode of extended keys.
-  if (!mIsExtended || !IsVistaOrLater()) {
+  if (!mIsExtended) {
     return mScanCode;
   }
   return (0xE000 | mScanCode);
@@ -1094,12 +1092,7 @@ bool
 NativeKey::CanComputeVirtualKeyCodeFromScanCode() const
 {
   // Vista or later supports ScanCodeEx.
-  if (IsVistaOrLater()) {
-    return true;
-  }
-  // Otherwise, MapVirtualKeyEx() can compute virtual keycode only with
-  // non-extended key.
-  return !mIsExtended;
+  return true;
 }
 
 uint8_t
@@ -1125,8 +1118,7 @@ NativeKey::ComputeScanCodeExFromVirtualKeyCode(UINT aVirtualKeyCode) const
 {
   return static_cast<uint16_t>(
            ::MapVirtualKeyEx(aVirtualKeyCode,
-                             IsVistaOrLater() ? MAPVK_VK_TO_VSC_EX :
-                                                MAPVK_VK_TO_VSC,
+                             MAPVK_VK_TO_VSC_EX,
                              mKeyboardLayout));
 }
 
@@ -2384,8 +2376,7 @@ KeyboardLayout::LoadLayout(HKL aLayout)
 #ifdef PR_LOGGING
   if (PR_LOG_TEST(sKeyboardLayoutLogger, PR_LOG_DEBUG)) {
     static const UINT kExtendedScanCode[] = { 0x0000, 0xE000 };
-    static const UINT kMapType =
-      IsVistaOrLater() ? MAPVK_VSC_TO_VK_EX : MAPVK_VSC_TO_VK;
+    static const UINT kMapType = MAPVK_VSC_TO_VK_EX;
     PR_LOG(sKeyboardLayoutLogger, PR_LOG_DEBUG,
            ("Logging virtual keycode values for scancode (0x%p)...",
             mKeyboardLayout));
@@ -2397,11 +2388,6 @@ KeyboardLayout::LoadLayout(HKL aLayout)
         PR_LOG(sKeyboardLayoutLogger, PR_LOG_DEBUG,
                ("0x%04X, %s", scanCode, kVirtualKeyName[virtualKeyCode]));
       }
-      // XP and Server 2003 don't support 0xE0 prefix of the scancode.
-      // Therefore, we don't need to continue on them.
-      if (!IsVistaOrLater()) {
-        break;
-      }
     }
   }
 #endif // #ifdef PR_LOGGING