Fix dumpsys meminfo <pid>.

Added a case for BumpPointerSpaces. Confirmed working non-debug.
Should also work in debug builds.

Bug: 11830794
Change-Id: I12053ff16eec403dcd4a780e13095e3212a77132
diff --git a/runtime/gc/space/bump_pointer_space.h b/runtime/gc/space/bump_pointer_space.h
index 9b0b6aa..2edd3e2 100644
--- a/runtime/gc/space/bump_pointer_space.h
+++ b/runtime/gc/space/bump_pointer_space.h
@@ -120,7 +120,11 @@
   static mirror::Object* GetNextObject(mirror::Object* obj)
       SHARED_LOCKS_REQUIRED(Locks::mutator_lock_);
 
-  // Alignment.
+  virtual BumpPointerSpace* AsBumpPointerSpace() {
+    return this;
+  }
+
+  // Object alignment within the space.
   static constexpr size_t kAlignment = 8;
 
  protected: