Reduce calls to DescriptorEquals

Store the low 3 bits of the descriptor hash inside of class set
entries. Compare these bits before comparing descriptors.

Simpleperf interpret-only compile of facebook:
mirror::Class::DescriptorEquals(char const*): 3.66% -> 1.03%

Bug: 32641252

Test: test-art-host

Change-Id: I8d898d4ac7c95383c49401fbcd85bfde226e026c
diff --git a/patchoat/patchoat.cc b/patchoat/patchoat.cc
index db28a3f..cb5a790 100644
--- a/patchoat/patchoat.cc
+++ b/patchoat/patchoat.cc
@@ -605,8 +605,7 @@
   ClassTable temp_table;
   temp_table.ReadFromMemory(image_->Begin() + section.Offset());
   FixupRootVisitor visitor(this);
-  BufferedRootVisitor<kDefaultBufferedRootCount> buffered_visitor(&visitor, RootInfo(kRootUnknown));
-  temp_table.VisitRoots(buffered_visitor);
+  temp_table.VisitRoots(UnbufferedRootVisitor(&visitor, RootInfo(kRootUnknown)));
 }