Implement large cursors in Mushrome.

services/ui/public/interfaces/cursor/cursor.mojom

Index: services/ui/public/interfaces/cursor/cursor.mojom
diff --git a/services/ui/public/interfaces/cursor/cursor.mojom b/services/ui/public/interfaces/cursor/cursor.mojom
index c228539ae9641913d92031ceb8c535cb22107f1e..a4f58063d16fb6fc3e8454f61717bf560763fd94 100644
--- a/services/ui/public/interfaces/cursor/cursor.mojom
+++ b/services/ui/public/interfaces/cursor/cursor.mojom
@@ -60,6 +60,13 @@ enum CursorType {
   kCustom
 };
 
+// Whether we use normal or large cursors. These are the same as Chrome's
+// ui::CursorSize.
+enum CursorSize {
+  kNormal,
+  kLarge
+};
+
 // A description of a cursor.
 struct CursorData {
   // The type of cursor. If CUSTOM, the rest of the fields are relevant.