Revert "Revert "Refactor GetIMTIndex""

Originally reverted in order to revert
https://android-review.googlesource.com/#/c/244190/
but can now be merged again.

This reverts commit d4ceecc85a5aab2ec23ea1bd010692ba8c8aaa0c.

Test: m test-art-host

Change-Id: Id9205f2b77a378fc0f06088e78c66e81a49f712d
diff --git a/runtime/art_method-inl.h b/runtime/art_method-inl.h
index 26450c4..32ae6ff 100644
--- a/runtime/art_method-inl.h
+++ b/runtime/art_method-inl.h
@@ -120,6 +120,10 @@
   return dex_method_index_;
 }
 
+inline uint32_t ArtMethod::GetImtIndex() {
+  return GetDexMethodIndex() % ImTable::kSize;
+}
+
 inline ArtMethod** ArtMethod::GetDexCacheResolvedMethods(size_t pointer_size) {
   return GetNativePointer<ArtMethod**>(DexCacheResolvedMethodsOffset(pointer_size),
                                        pointer_size);