Put inlined ArtMethod pointer in stack maps.

Currently done for JIT. Can be extended for AOT and inlined boot
image methods.

Also refactor the lookup of a inlined method at runtime to not
rely on the dex cache, but look at the class loader tables.

bug: 30933338
test: test-art-host, test-art-target
Change-Id: I58bd4d763b82ab8ca3023742835ac388671d1794
diff --git a/runtime/art_method-inl.h b/runtime/art_method-inl.h
index 96976d9..9c20740 100644
--- a/runtime/art_method-inl.h
+++ b/runtime/art_method-inl.h
@@ -121,7 +121,7 @@
 inline uint32_t ArtMethod::GetDexMethodIndex() {
   DCHECK(IsRuntimeMethod() || GetDeclaringClass()->IsIdxLoaded() ||
          GetDeclaringClass()->IsErroneous());
-  return dex_method_index_;
+  return GetDexMethodIndexUnchecked();
 }
 
 inline ArtMethod** ArtMethod::GetDexCacheResolvedMethods(PointerSize pointer_size) {