ART: Do some include-what-you-use

Help with transitive includes. In preparation for new
specialized headers reducing transitivity.

Bug: 118385392
Test: mmma art
Change-Id: Ie79afda4e09191428c2b4c2f20a7e3352c01c1e9
diff --git a/runtime/mirror/class.cc b/runtime/mirror/class.cc
index 6a378f0..e655052 100644
--- a/runtime/mirror/class.cc
+++ b/runtime/mirror/class.cc
@@ -32,6 +32,7 @@
 #include "dex/dex_file_annotations.h"
 #include "dex_cache.h"
 #include "gc/accounting/card_table-inl.h"
+#include "gc/heap-inl.h"
 #include "handle_scope-inl.h"
 #include "subtype_check.h"
 #include "method.h"