ClipData: add Sequence property (#497)

Simply missing from previous commits.

Author: jzoran

api/current.txt

@@ -22,6 +22,7 @@ package androidx.core.content {
     method public static void forEach(android.content.ClipData, kotlin.jvm.functions.Function1<? super android.content.ClipData.Item,kotlin.Unit> action);
     method public static void forEachIndexed(android.content.ClipData, kotlin.jvm.functions.Function2<? super java.lang.Integer,? super android.content.ClipData.Item,kotlin.Unit> action);
     method public static operator android.content.ClipData.Item get(android.content.ClipData, int index);
+    method public static kotlin.sequences.Sequence<android.content.ClipData.Item> getItems(android.content.ClipData);
     method public static operator java.util.Iterator<android.content.ClipData.Item> iterator(android.content.ClipData);
   }
 

src/androidTest/java/androidx/core/content/ClipDataTest.kt

@@ -108,6 +108,17 @@ class ClipDataTest {
         }
     }
 
+    @Test fun items() {
+        val itemsList = listOf(ClipData.Item(""), ClipData.Item(""))
+        itemsList.forEach { clip.addItem(it) }
+
+        clip.items.forEachIndexed { index, item ->
+            if (index != 0) {
+                assertSame(itemsList[index - 1], item)
+            }
+        }
+    }
+
     @Test fun map() {
         clip.addItem(ClipData.Item("item1"))
         clip.addItem(ClipData.Item("item2"))

src/main/java/androidx/core/content/ClipData.kt

@@ -65,6 +65,12 @@ operator fun ClipData.iterator() = object : Iterator<ClipData.Item> {
     override fun next() = getItemAt(index++) ?: throw IndexOutOfBoundsException()
 }
 
+/** Returns a [Sequence] over the items in this ClipData. */
+val ClipData.items: Sequence<ClipData.Item>
+    get() = object : Sequence<ClipData.Item> {
+        override fun iterator() = this@items.iterator()
+    }
+
 /**
  * Returns a [List] containing the results of applying the given transform function to each
  * item in this ClipData.