[turbofan] Make FieldAccess::name usable in practice.

test/unittests/compiler/escape-analysis-unittest.cc

Index: test/unittests/compiler/escape-analysis-unittest.cc
diff --git a/test/unittests/compiler/escape-analysis-unittest.cc b/test/unittests/compiler/escape-analysis-unittest.cc
index 17e0da44c98e57e6b36f99c9b8c6301f0f1f3872..0d3d008229c8ec053b26a9c46000e76597ccbd06 100644
--- a/test/unittests/compiler/escape-analysis-unittest.cc
+++ b/test/unittests/compiler/escape-analysis-unittest.cc
@@ -132,7 +132,7 @@ class EscapeAnalysisTest : public GraphTest {
   }
 
   FieldAccess AccessAtIndex(int offset) {
-    FieldAccess access = {kTaggedBase, offset, MaybeHandle<Name>(), Type::Any(),
+    FieldAccess access = {kTaggedBase, offset, nullptr, Type::Any(),
                           MachineType::AnyTagged()};
     return access;
   }