Fix rate limiting comparison

Also tweak deferred cleanup for persistent processes to reduce
total memory usage.

Bug: 275486055
Test: watching gfxinfo of sysui
Change-Id: Id679a43062941c096d437b76aebe1a5a9ca0b404
diff --git a/libs/hwui/MemoryPolicy.cpp b/libs/hwui/MemoryPolicy.cpp
index ca1312e7..21f4ca7 100644
--- a/libs/hwui/MemoryPolicy.cpp
+++ b/libs/hwui/MemoryPolicy.cpp
@@ -28,7 +28,10 @@
 constexpr static MemoryPolicy sDefaultMemoryPolicy;
 constexpr static MemoryPolicy sPersistentOrSystemPolicy{
         .contextTimeout = 10_s,
+        .minimumResourceRetention = 1_s,
+        .maximumResourceRetention = 10_s,
         .useAlternativeUiHidden = true,
+        .purgeScratchOnly = false,
 };
 constexpr static MemoryPolicy sLowRamPolicy{
         .useAlternativeUiHidden = true,