Revert "Create parent class loader for dex2oat"

Bug: 22858531

This reverts commit d37d364c27e74a7b49970a8c970482e273aa7b1a.

Change-Id: Id71a6f3bb9a29c04a5c13210633674e05d798114
diff --git a/runtime/class_linker.cc b/runtime/class_linker.cc
index 3d06295..ddd285a 100644
--- a/runtime/class_linker.cc
+++ b/runtime/class_linker.cc
@@ -6901,9 +6901,7 @@
   }
 }
 
-jobject ClassLinker::CreatePathClassLoader(Thread* self,
-                                           std::vector<const DexFile*>& dex_files,
-                                           jobject parent_loader) {
+jobject ClassLinker::CreatePathClassLoader(Thread* self, std::vector<const DexFile*>& dex_files) {
   // SOAAlreadyRunnable is protected, and we need something to add a global reference.
   // We could move the jobject to the callers, but all call-sites do this...
   ScopedObjectAccessUnchecked soa(self);
@@ -6934,8 +6932,8 @@
   for (const DexFile* dex_file : dex_files) {
     StackHandleScope<3> hs2(self);
 
-    // CreatePathClassLoader is only used by gtests and dex2oat. Index 0 of h_long_array is
-    // supposed to be the oat file but we can leave it null.
+    // CreatePathClassLoader is only used by gtests. Index 0 of h_long_array is supposed to be the
+    // oat file but we can leave it null.
     Handle<mirror::LongArray> h_long_array = hs2.NewHandle(mirror::LongArray::Alloc(
         self,
         kDexFileIndexStart + 1));
@@ -6981,10 +6979,9 @@
       mirror::Class::FindField(self, hs.NewHandle(h_path_class_loader->GetClass()), "parent",
                                "Ljava/lang/ClassLoader;");
   DCHECK(parent_field != nullptr);
-  mirror::Object* parent = (parent_loader != nullptr)
-      ? soa.Decode<mirror::ClassLoader*>(parent_loader)
-      : soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self);
-  parent_field->SetObject<false>(h_path_class_loader.Get(), parent);
+  mirror::Object* boot_cl =
+      soa.Decode<mirror::Class*>(WellKnownClasses::java_lang_BootClassLoader)->AllocObject(self);
+  parent_field->SetObject<false>(h_path_class_loader.Get(), boot_cl);
 
   // Make it a global ref and return.
   ScopedLocalRef<jobject> local_ref(