Automated rollback of commit e1b16e2.

*** Reason for rollback ***

Causes errors when building

`[ThreadSafe] @ThreadSafeTypeParameter is only supported on threadsafe classes`

*** Original change description ***

`@ImmutableTypeParameter` is really a subset of `@ThreadSafeTypeParameter`, much as `@Immutable` is a subset of `@ThreadSafe`.

***

PiperOrigin-RevId: 798434994

Author: kluever

core/src/main/java/com/google/errorprone/bugpatterns/threadsafety/ThreadSafety.java

@@ -32,7 +32,6 @@
 import com.google.errorprone.VisitorState;
 import com.google.errorprone.annotations.CanIgnoreReturnValue;
 import com.google.errorprone.annotations.Immutable;
-import com.google.errorprone.annotations.ImmutableTypeParameter;
 import com.google.errorprone.annotations.ThreadSafe;
 import com.google.errorprone.annotations.ThreadSafeTypeParameter;
 import com.google.errorprone.bugpatterns.CanBeStaticAnalyzer;
@@ -95,10 +94,7 @@ public static ThreadSafety.Builder threadSafeBuilder(
             .knownTypes(wellKnownThreadSafety)
             .markerAnnotations(ImmutableSet.of(ThreadSafe.class.getName()))
             .acceptedAnnotations(ImmutableSet.of(Immutable.class.getName()))
-            .typeParameterAnnotation(
-                ImmutableSet.of(
-                    ThreadSafeTypeParameter.class.getName(),
-                    ImmutableTypeParameter.class.getName()));
+            .typeParameterAnnotation(ImmutableSet.of(ThreadSafeTypeParameter.class.getName()));
     return builder;
   }
 

core/src/test/java/com/google/errorprone/bugpatterns/threadsafety/ThreadSafeCheckerTest.java

@@ -1353,23 +1353,6 @@ class Test<@ThreadSafeTypeParameter T> {
         .doTest();
   }
 
-  @Test
-  public void immutableTypeParam_alsoThreadSafe() {
-    compilationHelper
-        .addSourceLines(
-            "Test.java",
-            """
-            import com.google.errorprone.annotations.ThreadSafe;
-            import com.google.errorprone.annotations.ImmutableTypeParameter;
-
-            @ThreadSafe
-            class Test<@ImmutableTypeParameter T> {
-              final T t = null;
-            }
-            """)
-        .doTest();
-  }
-
   @Test
   public void threadSafeTypeParameterInstantiation() {
     compilationHelper