Allow a root activity to relinquish task identity

If a an acitivty with attribute android:relinquishTaskIdentity true
is the root activity of a task then the intent of that task will
be that of the first activity in the stack with
android:relinquishTaskIdentity set false.

The ability to set intent also includes the ability to set the
TaskDescription of the task.

Fixes bug 15675610.
Fixes bug 10428661.

Change-Id: Ib28a9eae3b9832eeeef9106adbebe344184ee5ae
diff --git a/core/java/android/content/pm/PackageParser.java b/core/java/android/content/pm/PackageParser.java
index 0b336d0..b40a441 100644
--- a/core/java/android/content/pm/PackageParser.java
+++ b/core/java/android/content/pm/PackageParser.java
@@ -2629,6 +2629,12 @@
                     false)) {
                 a.info.flags |= ActivityInfo.FLAG_AUTO_REMOVE_FROM_RECENTS;
             }
+
+            if (sa.getBoolean(
+                    com.android.internal.R.styleable.AndroidManifestActivity_relinquishTaskIdentity,
+                    false)) {
+                a.info.flags |= ActivityInfo.FLAG_RELINQUISH_TASK_IDENTITY;
+            }
         } else {
             a.info.launchMode = ActivityInfo.LAUNCH_MULTIPLE;
             a.info.configChanges = 0;