Add HeapTest and make GC work enough to pass it

Change-Id: If06eaef2921b64b3226bfd347acaec60ec993e67
diff --git a/src/compiler/Frontend.cc b/src/compiler/Frontend.cc
index 6c31cfe..9ef2b4f 100644
--- a/src/compiler/Frontend.cc
+++ b/src/compiler/Frontend.cc
@@ -18,6 +18,7 @@
 #include "CompilerInternals.h"
 #include "Dataflow.h"
 #include "constants.h"
+#include "runtime.h"
 
 static inline bool contentIsInsn(const u2* codePtr) {
     u2 instr = *codePtr;