Re-enable r8 optimization in IntentResolver

The previous "un-kept symbol" problem (with ChooserGridLayoutAdapter)
was inadvertently fixed by ag/20120577 (confirmed by going back to
check `apkdiffstats` before-and-after to note that the old crash is
due to a method that was only "un-kept" in the old version that still
shared framework RecyclerView). Manual review of other un-kept
symbols under `com.android.intentresolver.*` all seemed reasonable in
this new CL. For more info, see discussion on b/249159065.

Bug: 249159065, 249081140
Test: manual, and `atest IntentResolverUnitTests`
Change-Id: Ia6cf5dd80ba3ec16038225ccdac5203782c3db1f
diff --git a/Android.bp b/Android.bp
index 2477d40..c2866f8 100644
--- a/Android.bp
+++ b/Android.bp
@@ -71,10 +71,7 @@
         "IntentResolver-core",
     ],
     optimize: {
-        // TODO: consider re-enabling after setting up Proguard rules to
-        // preserve the name of the ChooserGridLayoutManager class, which is
-        // referenced by name in the chooser_list_per_profile layout XML.
-        enabled: false,
+        enabled: true,
     },
     apex_available: [
         "//apex_available:platform",