Update CPA startActivity javadoc to refer to passing the result back

Update both versions of CrossProfileApps#startActivity to refer to
passing the result back to the passed in calling activity.

Bug: 174506563
Fixes: 171957840
Test: atest com.android.cts.devicepolicy.CrossProfileAppsHostSideTest#testStartActivityIntent_crossProfile_returnsResult
Change-Id: I14bf779d9307232b31300b828a1606c7411c7bb3
diff --git a/core/java/android/content/pm/CrossProfileApps.java b/core/java/android/content/pm/CrossProfileApps.java
index 3b6740e..f6fa6dd 100644
--- a/core/java/android/content/pm/CrossProfileApps.java
+++ b/core/java/android/content/pm/CrossProfileApps.java
@@ -119,8 +119,9 @@
      *        {@link #getTargetUserProfiles()} if different to the calling user, otherwise a
      *        {@link SecurityException} will be thrown.
      * @param callingActivity The activity to start the new activity from for the purposes of
-     *        deciding which task the new activity should belong to. If {@code null}, the activity
-     *        will always be started in a new task.
+     *        passing back any result and deciding which task the new activity should belong to. If
+     *        {@code null}, the activity will always be started in a new task and no result will be
+     *        returned.
      */
     @RequiresPermission(anyOf = {
             android.Manifest.permission.INTERACT_ACROSS_PROFILES,
@@ -146,8 +147,9 @@
      *        {@link #getTargetUserProfiles()} if different to the calling user, otherwise a
      *        {@link SecurityException} will be thrown.
      * @param callingActivity The activity to start the new activity from for the purposes of
-     *        deciding which task the new activity should belong to. If {@code null}, the activity
-     *        will always be started in a new task.
+     *        passing back any result and deciding which task the new activity should belong to. If
+     *        {@code null}, the activity will always be started in a new task and no result will be
+     *        returned.
      * @param options The activity options or {@code null}. See {@link android.app.ActivityOptions}.
      */
     @RequiresPermission(anyOf = {