Revert "Basic obsolete methods support"

This reverts commit d8936da27b792d1ca02e59c92456a1a53c7b9905.

Reason for revert: Some sort of race in JIT

Change-Id: Ibb4e520bb0721d6d7aa2c841a52eb5baff07740e
diff --git a/runtime/mirror/dex_cache.h b/runtime/mirror/dex_cache.h
index 6f88cc5..ec265e5 100644
--- a/runtime/mirror/dex_cache.h
+++ b/runtime/mirror/dex_cache.h
@@ -19,6 +19,7 @@
 
 #include "array.h"
 #include "art_field.h"
+#include "art_method.h"
 #include "class.h"
 #include "dex_file_types.h"
 #include "object.h"
@@ -26,7 +27,6 @@
 
 namespace art {
 
-class ArtMethod;
 struct DexCacheOffsets;
 class DexFile;
 class ImageWriter;