Delete ArtMethod gc_map_ field

Moved the gc_map field from OatMethod to OatQuickMethodHeader.
Deleted the ArtMethod gc_map_ field.

Bug: 17643507

Change-Id: Ifa0470c3e4c2f8a319744464d94c6838b76b3d48

(cherry picked from commit 807140048f82a2b87ee5bcf337f23b6a3d1d5269)
diff --git a/runtime/thread.cc b/runtime/thread.cc
index 163c11d..f7c7106 100644
--- a/runtime/thread.cc
+++ b/runtime/thread.cc
@@ -2102,7 +2102,7 @@
     } else {
       // Java method.
       // Portable path use DexGcMap and store in Method.native_gc_map_.
-      const uint8_t* gc_map = m->GetNativeGcMap();
+      const uint8_t* gc_map = m->GetNativeGcMap(sizeof(void*));
       CHECK(gc_map != nullptr) << PrettyMethod(m);
       verifier::DexPcToReferenceMap dex_gc_map(gc_map);
       uint32_t dex_pc = shadow_frame->GetDexPC();
@@ -2157,7 +2157,7 @@
           }
         }
       } else {
-        const uint8_t* native_gc_map = m->GetNativeGcMap();
+        const uint8_t* native_gc_map = m->GetNativeGcMap(sizeof(void*));
         CHECK(native_gc_map != nullptr) << PrettyMethod(m);
         const DexFile::CodeItem* code_item = m->GetCodeItem();
         // Can't be nullptr or how would we compile its instructions?