Fix coverage problem for window manager flag in shell

Bug: 315814188
Flag: NONE
Test: atest AppHibernationIntegrationTest
Change-Id: Ib6a31bb92d1e53d0d45073a5a271df73c136a620
diff --git a/packages/SystemUI/proguard_common.flags b/packages/SystemUI/proguard_common.flags
index 21b019e..f9546c4 100644
--- a/packages/SystemUI/proguard_common.flags
+++ b/packages/SystemUI/proguard_common.flags
@@ -38,6 +38,11 @@
 -keepnames class com.android.internal.protolog.** { *; }
 -keepnames class android.hardware.common.** { *; }
 
+# TODO(b/316553881): Statically linking flags into SystemUI and bootclasspath might not be a
+# good idea in the first place
+-keepnames class com.android.window.flags.Flags { public *; }
+
+
 # Allows proguard to make private and protected methods and fields public as
 # part of optimization. This lets proguard inline trivial getter/setter methods.
 -allowaccessmodification