[WIP] JSForInLowering and JSForInHasOwnProperty.

src/compiler/access-builder.cc

Index: src/compiler/access-builder.cc
diff --git a/src/compiler/access-builder.cc b/src/compiler/access-builder.cc
index 2722590c76b9486001777545ffd27efa8fae2d95..c8f32f74a5031c37c8dbb07d5e923f9992b729cd 100644
--- a/src/compiler/access-builder.cc
+++ b/src/compiler/access-builder.cc
@@ -422,6 +422,16 @@ FieldAccess AccessBuilder::ForDescriptorArrayEnumCacheBridgeCache() {
   return access;
 }
 
+// static
+FieldAccess AccessBuilder::ForDescriptorArrayEnumCacheBridgeIndicesCache() {
+  // TODO(bmeurer): Weird hack!
+  FieldAccess access = {
+      kTaggedBase,      DescriptorArray::kEnumCacheBridgeIndicesCacheOffset,
+      Handle<Name>(),   MaybeHandle<Map>(),
+      Type::Any(),      MachineType::AnyTagged(),
+      kFullWriteBarrier};
+  return access;
+}
 
 // static
 FieldAccess AccessBuilder::ForMapBitField() {