Change ArtField::ProxyFindSystemClass() to lookup the class.

As the function is called from ArtField::LookupType(),
we should avoid calls that appear to allow type resolution
rather than plain lookup. The lookup should always succeed.

Also rename ArtField::LookupType() to LookupResolvedType()
to align with naming used in ClassLinker and ArtMethod.

Test: m test-art-host-gtest
Test: testrunner.py --host --optimizing
Change-Id: I0a87347b5341575e47e0fdba6d58ade2543387c8
diff --git a/runtime/art_field-inl.h b/runtime/art_field-inl.h
index 4a328e8..ae81ee8 100644
--- a/runtime/art_field-inl.h
+++ b/runtime/art_field-inl.h
@@ -299,7 +299,7 @@
   return GetTypeAsPrimitiveType() != Primitive::kPrimNot;
 }
 
-inline ObjPtr<mirror::Class> ArtField::LookupType() {
+inline ObjPtr<mirror::Class> ArtField::LookupResolvedType() {
   ScopedAssertNoThreadSuspension ants(__FUNCTION__);
   const uint32_t field_index = GetDexFieldIndex();
   ObjPtr<mirror::Class> declaring_class = GetDeclaringClass();