[dart:html] Remove duplicate switch case

Fixes #51754

META and WIN_KEY_LEFT have the same value. The switch case for the
second value is never triggered, so we should remove it.

CoreLibraryReviewExempt: No functional change, just silencing warnings.
Change-Id: I51afe53a3d41e2c2fa820c2bb16e1bdea4583fac
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/290702
Commit-Queue: Srujan Gaddam <[email protected]>
Reviewed-by: Johnni Winther <[email protected]>

Author: srujzs

sdk/lib/html/dart2js/html_dart2js.dart

@@ -38067,7 +38067,7 @@ abstract class KeyCode {
   static const int Y = 89;
   static const int Z = 90;
   static const int META = 91;
-  static const int WIN_KEY_LEFT = 91;
+  static const int WIN_KEY_LEFT = 91; // Note that it's the same value as META.
   static const int WIN_KEY_RIGHT = 92;
   static const int CONTEXT_MENU = 93;
   static const int NUM_ZERO = 96;
@@ -38292,7 +38292,8 @@ abstract class KeyCode {
         return _KeyName.UP;
       case KeyCode.WIN_IME:
       case KeyCode.WIN_KEY:
-      case KeyCode.WIN_KEY_LEFT:
+      // Covered by `KeyCode.META` above.
+      // case KeyCode.WIN_KEY_LEFT:
       case KeyCode.WIN_KEY_RIGHT:
         return _KeyName.WIN;
       default:

tools/dom/src/KeyCode.dart

@@ -95,7 +95,7 @@ abstract class KeyCode {
   static const int Y = 89;
   static const int Z = 90;
   static const int META = 91;
-  static const int WIN_KEY_LEFT = 91;
+  static const int WIN_KEY_LEFT = 91; // Note that it's the same value as META.
   static const int WIN_KEY_RIGHT = 92;
   static const int CONTEXT_MENU = 93;
   static const int NUM_ZERO = 96;
@@ -320,7 +320,8 @@ abstract class KeyCode {
         return _KeyName.UP;
       case KeyCode.WIN_IME:
       case KeyCode.WIN_KEY:
-      case KeyCode.WIN_KEY_LEFT:
+      // Covered by `KeyCode.META` above.
+      // case KeyCode.WIN_KEY_LEFT:
       case KeyCode.WIN_KEY_RIGHT:
         return _KeyName.WIN;
       default: