API validator fixes

Author: Dmytro Ivanov

Diff for: Assets/Tests/InputSystem/APIVerificationTests.cs

@@ -424,6 +424,10 @@ public class SwitchProControllerHID : UnityEngine.InputSystem.Gamepad
     [Property("Exclusions", @"1.0.0
         public class DualShock4GamepadHID : UnityEngine.InputSystem.DualShock.DualShockGamepad
     ")]
+    // IMECompositionEvent.compositionString changed from field to property due to hard-to-avoid changes to IMECompositionString struct.
+    [Property("Exclusions", @"1.0.0
+        public struct IMECompositionEvent : UnityEngine.InputSystem.LowLevel.IInputEventTypeInfo
+    ")]
     public void API_MinorVersionsHaveNoBreakingChanges()
     {
         var currentVersion = CoreTests.PackageJson.ReadVersion();

Diff for: Packages/com.unity.inputsystem/InputSystem/Events/IMECompositionEvent.cs

@@ -6,8 +6,14 @@
 using Unity.Collections.LowLevel.Unsafe;
 using UnityEngine.InputSystem.Utilities;
 
+//// TODO for v2 remove and replace with just string.
+
 namespace UnityEngine.InputSystem.LowLevel
 {
+    /// <summary>
+    /// Deprecated variant of IME composition event. Please use <see cref="IMECompositionEventVariableSize"/> for replacement.
+    /// </summary>
+    /// <see cref="IMECompositionEventVariableSize"/>
     [Obsolete("IMECompositionEvent is obsolete, please use IMECompositionEventVariableSize")]
     [StructLayout(LayoutKind.Explicit, Size = InputEvent.kBaseEventSize + sizeof(int) + (sizeof(char) * kIMECharBufferSize))]
     public unsafe struct IMECompositionEvent : IInputEventTypeInfo
@@ -108,7 +114,6 @@ public static unsafe void QueueEvent(int deviceId, string str, double time)
         }
     }
 
-    //// TODO for v2 remove and replace with just string.
     /// <summary>
     /// A struct representing an string of characters generated by an IME for text input.
     /// </summary>