Style cleanup for ObjPtr<>-ify changes.

Replace "ObjPtr<.> const" with "const ObjPtr<.>".

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Bug: 31113334
Change-Id: I5a1c080bc88b091e15ee9eb0bb1ef6f6f290701c
diff --git a/runtime/class_table-inl.h b/runtime/class_table-inl.h
index a2cdb2c..5f8a0b0 100644
--- a/runtime/class_table-inl.h
+++ b/runtime/class_table-inl.h
@@ -91,8 +91,8 @@
 template<ReadBarrierOption kReadBarrierOption>
 inline mirror::Class* ClassTable::TableSlot::Read() const {
   const uint32_t before = data_.load(std::memory_order_relaxed);
-  ObjPtr<mirror::Class> const before_ptr(ExtractPtr(before));
-  ObjPtr<mirror::Class> const after_ptr(
+  const ObjPtr<mirror::Class> before_ptr(ExtractPtr(before));
+  const ObjPtr<mirror::Class> after_ptr(
       GcRoot<mirror::Class>(before_ptr).Read<kReadBarrierOption>());
   if (kReadBarrierOption != kWithoutReadBarrier && before_ptr != after_ptr) {
     // If another thread raced and updated the reference, do not store the read barrier updated