IdentifierName: don't crash on receiver parameters

core/src/main/java/com/google/errorprone/bugpatterns/IdentifierName.java

@@ -199,7 +199,8 @@ public Description matchVariable(VariableTree tree, VisitorState state) {
         if (NamedParameterComment.containsSyntheticParameterName(superMethod)) {
           return NO_MATCH;
         }
-        if (index < superMethod.getParameters().size()
+        if (index >= 0
+            && index < superMethod.getParameters().size()
             && superMethod.getParameters().get(index).getSimpleName().contentEquals(name)) {
           return NO_MATCH;
         }

core/src/test/java/com/google/errorprone/bugpatterns/IdentifierNameTest.java

@@ -778,4 +778,25 @@ class Murmur3_32 {}
             """)
         .doTest();
   }
+
+  @Test
+  public void receiverParameter() {
+    helper
+        .addSourceLines(
+            "Super.java",
+            """
+            class Super {
+              void test(int x) {}
+            }
+            """)
+        .addSourceLines(
+            "Test.java",
+            """
+            class Test extends Super {
+              @Override
+              void test(Test this, int x) {}
+            }
+            """)
+        .doTest();
+  }
 }