Remove workaround for [ancient Android unmodifiableMap bug](https:/…

…/issuetracker.google.com/36997692).

[The fix](https://android-review.googlesource.com/c/platform/libcore/+/98929) is [present](https://cs.android.com/android/platform/superproject/+/android-5.0.2_r3:libcore/luni/src/main/java/java/util/Collections.java;l=1215;drc=244e90adfe67264364de88df0fd741db0eb12b7f) in time for [Lollipop](https://source.android.com/docs/setup/reference/build-numbers), the oldest version [we currently test under](https://github.com/google/guava?tab=readme-ov-file#important-warnings).

RELNOTES=n/a
PiperOrigin-RevId: 642003868

android/guava-testlib/src/com/google/common/collect/testing/google/UnmodifiableCollectionTests.java

@@ -22,7 +22,6 @@
 
 import com.google.common.annotations.GwtCompatible;
 import com.google.common.collect.ArrayListMultimap;
-import com.google.common.collect.Iterators;
 import com.google.common.collect.LinkedHashMultiset;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
@@ -120,9 +119,7 @@ public static void assertIteratorsInOrder(
     siblingCollection.add(sampleElement);
 
     Collection<E> copy = new ArrayList<>();
-    // Avoid copy.addAll(collection), which runs afoul of an Android bug in older versions:
-    // http://b.android.com/72073 http://r.android.com/98929
-    Iterators.addAll(copy, collection.iterator());
+    copy.addAll(collection);
 
     try {
       collection.add(sampleElement);

guava-testlib/src/com/google/common/collect/testing/google/UnmodifiableCollectionTests.java

@@ -22,7 +22,6 @@
 
 import com.google.common.annotations.GwtCompatible;
 import com.google.common.collect.ArrayListMultimap;
-import com.google.common.collect.Iterators;
 import com.google.common.collect.LinkedHashMultiset;
 import com.google.common.collect.Lists;
 import com.google.common.collect.Maps;
@@ -120,9 +119,7 @@ public static void assertIteratorsInOrder(
     siblingCollection.add(sampleElement);
 
     Collection<E> copy = new ArrayList<>();
-    // Avoid copy.addAll(collection), which runs afoul of an Android bug in older versions:
-    // http://b.android.com/72073 http://r.android.com/98929
-    Iterators.addAll(copy, collection.iterator());
+    copy.addAll(collection);
 
     try {
       collection.add(sampleElement);