Build failure after JDK-8252481

Seem to be caused by JDK-8252481.

/home/shade/trunks/jdk-jdk/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp: In member function 'virtual jint ShenandoahHeap::initialize()':
/home/shade/trunks/jdk-jdk/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp:232:15: error: incomplete type 'MemTracker' used in nested name specifier
  232 | MemTracker::record_virtual_memory_type(bitmap.base(), mtGC);
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~
/home/shade/trunks/jdk-jdk/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp:252:17: error: incomplete type 'MemTracker' used in nested name specifier
  252 | MemTracker::record_virtual_memory_type(verify_bitmap.base(), mtGC);
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~
/home/shade/trunks/jdk-jdk/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp:260:15: error: incomplete type 'MemTracker' used in nested name specifier
  260 | MemTracker::record_virtual_memory_type(aux_bitmap.base(), mtGC);
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~
/home/shade/trunks/jdk-jdk/src/hotspot/share/gc/shenandoah/shenandoahHeap.cpp:273:15: error: incomplete type 'MemTracker' used in nested name specifier
  273 | MemTracker::record_virtual_memory_type(region_storage.base(), mtGC);
      | ^~~~~~~~~~~~~~~~~~~~~~~~~~