For #11666 - Add PendingUtils.defaultFlags helper

components/support/utils/src/main/java/mozilla/components/support/utils/PendingIntentUtils.kt

@@ -0,0 +1,28 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.components.support.utils
+
+import android.app.PendingIntent
+import android.os.Build
+
+/**
+ * Helper methods for when working with [PendingIntent]s.
+ */
+object PendingIntentUtils {
+    /**
+     * Android 6 introduced FLAG_IMMUTABLE to prevents apps that receive a PendingIntent from
+     * filling in unpopulated properties. Android 12 requires mutability explicitly.
+     *
+     * This property will return:
+     * - PendingIntent.FLAG_IMMUTABLE - for Android API 23+
+     * - 0 (framework default flags) - for Android APIs lower than 23.
+     */
+    val defaultFlags
+        get() = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
+            PendingIntent.FLAG_IMMUTABLE
+        } else {
+            0 // No flags. Default behavior.
+        }
+}

components/support/utils/src/test/java/mozilla/components/support/utils/PendingIntentUtilsTest.kt

@@ -0,0 +1,28 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+package mozilla.components.support.utils
+
+import android.app.PendingIntent
+import android.os.Build
+import androidx.test.ext.junit.runners.AndroidJUnit4
+import org.junit.Assert.assertEquals
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.robolectric.annotation.Config
+
+@RunWith(AndroidJUnit4::class)
+class PendingIntentUtilsTest {
+    @Test
+    @Config(sdk = [Build.VERSION_CODES.LOLLIPOP_MR1]) // highest API level for which to return 0
+    fun `GIVEN an Android L device WHEN defaultFlags is called THEN return 0`() {
+        assertEquals(0, PendingIntentUtils.defaultFlags)
+    }
+
+    @Test
+    @Config(sdk = [Build.VERSION_CODES.M]) // first API level for which to return FLAG_IMMUTABLE
+    fun `GIVEN an Android M device WHEN defaultFlags is called THEN return FLAG_IMMUTABLE`() {
+        assertEquals(PendingIntent.FLAG_IMMUTABLE, PendingIntentUtils.defaultFlags)
+    }
+}

docs/changelog.md

@@ -11,6 +11,9 @@ permalink: /changelog/
 * [Gecko](https://github.com/mozilla-mobile/android-components/blob/main/buildSrc/src/main/java/Gecko.kt)
 * [Configuration](https://github.com/mozilla-mobile/android-components/blob/main/.config.yml)
 
+* **support-utils**
+  * 🌟️️ **Add a `PendingUtils.defaultFlags` property to ease setting PendingIntent mutability as required for Android 31+.
+
 * **feature-prompts**:
   * More prompts are dismissable.
   * **Breaking change:** Success / dismiss callbacks are now consistently