Fix example in documentation for IteratorTester

I made a mistake and accidentally included an example that does not
compile. Specifically, importing `KnownOrder` as-is does not compile;
instead one needs to import `IteratorTester.KnownOrder`. See #5254 for
more information.

I also changed the example to use `Collections#unmodifiableList`
rather than `ArrayList` because `ArrayList#iterator` does not satisfy
all the requirements of `IteratorFeature#MODIFIABLE`.

Fixes #5276

RELNOTES=n/a

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=336911192

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

@@ -50,19 +50,21 @@
  * verify() method, which is called <em>after</em> each sequence and is guaranteed to be called
  * using the latest values obtained from {@link IteratorTester#newTargetIterator()}.
  *
- * <p>For example, to test {@link java.util.ArrayList#iterator() ArrayList.iterator()}:
+ * <p>For example, to test {@link java.util.Collections#unmodifiableList(java.util.List)
+ * Collections.unmodifiableList}'s iterator:
  *
  * <pre>{@code
  * List<String> expectedElements =
  *     Arrays.asList("a", "b", "c", "d", "e");
  * List<String> actualElements =
- *     new ArrayList<>(Arrays.asList("a", "b", "c", "d", "e"));
+ *     Collections.unmodifiableList(
+ *         Arrays.asList("a", "b", "c", "d", "e"));
  * IteratorTester<String> iteratorTester =
  *     new IteratorTester<String>(
  *         5,
- *         IteratorFeature.MODIFIABLE,
+ *         IteratorFeature.UNMODIFIABLE,
  *         expectedElements,
- *         KnownOrder.KNOWN_ORDER) {
+ *         IteratorTester.KnownOrder.KNOWN_ORDER) {
  *       @Override
  *       protected Iterator<String> newTargetIterator() {
  *         return actualElements.iterator();
@@ -72,6 +74,9 @@
  * iteratorTester.testForEachRemaining();
  * }</pre>
  *
+ * <p><b>Note</b>: It is necessary to use {@code IteratorTester.KnownOrder} as shown above, rather
+ * than {@code KnownOrder} directly, because otherwise the code is not compilable.
+ *
  * @author Kevin Bourrillion
  * @author Chris Povirk
  */

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

@@ -50,19 +50,21 @@
  * verify() method, which is called <em>after</em> each sequence and is guaranteed to be called
  * using the latest values obtained from {@link IteratorTester#newTargetIterator()}.
  *
- * <p>For example, to test {@link java.util.ArrayList#iterator() ArrayList.iterator()}:
+ * <p>For example, to test {@link java.util.Collections#unmodifiableList(java.util.List)
+ * Collections.unmodifiableList}'s iterator:
  *
  * <pre>{@code
  * List<String> expectedElements =
  *     Arrays.asList("a", "b", "c", "d", "e");
  * List<String> actualElements =
- *     new ArrayList<>(Arrays.asList("a", "b", "c", "d", "e"));
+ *     Collections.unmodifiableList(
+ *         Arrays.asList("a", "b", "c", "d", "e"));
  * IteratorTester<String> iteratorTester =
  *     new IteratorTester<String>(
  *         5,
- *         IteratorFeature.MODIFIABLE,
+ *         IteratorFeature.UNMODIFIABLE,
  *         expectedElements,
- *         KnownOrder.KNOWN_ORDER) {
+ *         IteratorTester.KnownOrder.KNOWN_ORDER) {
  *       @Override
  *       protected Iterator<String> newTargetIterator() {
  *         return actualElements.iterator();
@@ -72,6 +74,9 @@
  * iteratorTester.testForEachRemaining();
  * }</pre>
  *
+ * <p><b>Note</b>: It is necessary to use {@code IteratorTester.KnownOrder} as shown above, rather
+ * than {@code KnownOrder} directly, because otherwise the code is not compilable.
+ *
  * @author Kevin Bourrillion
  * @author Chris Povirk
  */