Revert "Disable kBssEntry LoadString sharpening."

Fix .bss GC root walking by registering the oat file
with the class loader's class table.

Also fix potentially outdated ObjPtr<> use in debug build.

This reverts commit b55fdbb30b3bc4e334c241153b98c0a6ea4a4a2b.

Test: m test-art-host
Bug: 32124939
Change-Id: I0b7e3b93cb53c7b22408aa10a04eaf5582c69ee8
diff --git a/runtime/class_table.h b/runtime/class_table.h
index 1344990..bc9eaf4 100644
--- a/runtime/class_table.h
+++ b/runtime/class_table.h
@@ -141,6 +141,11 @@
       REQUIRES(!lock_)
       REQUIRES_SHARED(Locks::mutator_lock_);
 
+  // Return true if we inserted the oat file, false if it already exists.
+  bool InsertOatFile(const OatFile* oat_file)
+      REQUIRES(!lock_)
+      REQUIRES_SHARED(Locks::mutator_lock_);
+
   // Combines all of the tables into one class set.
   size_t WriteToMemory(uint8_t* ptr) const
       REQUIRES(!lock_)
@@ -168,6 +173,11 @@
  private:
   void InsertWithoutLocks(ObjPtr<mirror::Class> klass) NO_THREAD_SAFETY_ANALYSIS;
 
+  // Return true if we inserted the oat file, false if it already exists.
+  bool InsertOatFileLocked(const OatFile* oat_file)
+      REQUIRES(lock_)
+      REQUIRES_SHARED(Locks::mutator_lock_);
+
   // Lock to guard inserting and removing.
   mutable ReaderWriterMutex lock_;
   // We have a vector to help prevent dirty pages after the zygote forks by calling FreezeSnapshot.