Revert "HULK SMASH! We've gotta declare REL."

This reverts commit 90153d67e0.

Reason for revert: Temporary fix no longer needed; this was only added until an updated prebuilt for the referenced package was merged
Bug: 171506470
Test: none

Change-Id: Ibd3fec1d2ecd505693b4cf89ee8323eb8a50a604

core/java/android/app/PendingIntent.java

@@ -365,7 +365,6 @@ public final class PendingIntent implements Parcelable {
         }
 
         if (Compatibility.isChangeEnabled(PENDING_INTENT_EXPLICIT_MUTABILITY_REQUIRED)
-                && !"com.google.android.apps.gcs".equals(packageName)
                 && !flagImmutableSet && !flagMutableSet) {
             String msg = packageName + ": Targeting S+ (version " + Build.VERSION_CODES.S
                     + " and above) requires that one of FLAG_IMMUTABLE or FLAG_MUTABLE"