[java] JSpecify annotations for ScriptKey and UnpinnedScriptKey (#16483)

Co-authored-by: Diego Molina <[email protected]>

Author: mk868

java/src/org/openqa/selenium/ScriptKey.java

@@ -18,8 +18,11 @@
 package org.openqa.selenium;
 
 import java.util.Objects;
+import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
 import org.openqa.selenium.internal.Require;
 
+@NullMarked
 public class ScriptKey {
 
   private final String identifier;
@@ -33,7 +36,7 @@ public String getIdentifier() {
   }
 
   @Override
-  public boolean equals(Object o) {
+  public boolean equals(@Nullable Object o) {
     if (!(o instanceof ScriptKey)) {
       return false;
     }

java/src/org/openqa/selenium/UnpinnedScriptKey.java

@@ -23,13 +23,16 @@
 import java.util.Set;
 import java.util.UUID;
 import java.util.WeakHashMap;
+import org.jspecify.annotations.NullMarked;
+import org.jspecify.annotations.Nullable;
 
+@NullMarked
 public class UnpinnedScriptKey extends ScriptKey {
 
   private static final WeakHashMap<JavascriptExecutor, Set<UnpinnedScriptKey>> pinnedScripts =
       new WeakHashMap<>();
   private final String script;
-  private String scriptId;
+  private @Nullable String scriptId;
   private final String scriptHandle;
 
   static UnpinnedScriptKey pin(JavascriptExecutor executor, String script) {
@@ -61,11 +64,11 @@ public UnpinnedScriptKey(String script) {
     this.script = script;
   }
 
-  public void setScriptId(String id) {
+  public void setScriptId(@Nullable String id) {
     this.scriptId = id;
   }
 
-  public String getScriptId() {
+  public @Nullable String getScriptId() {
     return this.scriptId;
   }
 
@@ -91,7 +94,7 @@ public String removalScript() {
   }
 
   @Override
-  public boolean equals(Object o) {
+  public boolean equals(@Nullable Object o) {
     if (this == o) {
       return true;
     }