Revert^2 "Enable R8 full mode by default with SystemUI"

Reason for revert: CtsTileServiceTestCases failures
have been addressed.

8e7e99759f7ad7b92cce6c14355bb5e5d5a625ed

Change-Id: Ifb91730f5df6d5bc9bc533c7762f7b9ed1388dab
Bug: 215530220
diff --git a/packages/SystemUI/Android.bp b/packages/SystemUI/Android.bp
index 046706d..4aa4006 100644
--- a/packages/SystemUI/Android.bp
+++ b/packages/SystemUI/Android.bp
@@ -274,10 +274,12 @@
                 enabled: true,
                 optimize: true,
                 shrink: true,
+                proguard_compatibility: false,
                 proguard_flags_files: ["proguard.flags"],
             },
             conditions_default: {
                 optimize: {
+                    proguard_compatibility: false,
                     proguard_flags_files: ["proguard.flags"],
                 },
             },