Remove unsupported option from R8 flags

See I71cd2d0e54f24c61043ac0a67df0a22c1e74deb3

Bug: 112338230
Change-Id: Ia4f19555fb86464c19d3e9cd07cba1870b215181
diff --git a/core/proguard_basic_keeps.flags b/core/proguard_basic_keeps.flags
index 256b2ec..a0f577d 100644
--- a/core/proguard_basic_keeps.flags
+++ b/core/proguard_basic_keeps.flags
@@ -1,6 +1,3 @@
-# To prevent name conflict in incremental obfuscation.
--useuniqueclassmembernames
-
 # Some classes in the libraries extend package private classes to chare common functionality
 # that isn't explicitly part of the API
 -dontskipnonpubliclibraryclasses -dontskipnonpubliclibraryclassmembers