Use TestNamer in HLSL tests.

This CL updates the HLSL tests to use the test namer and fixes up places
where the incorrect name was output.

Change-Id: I8510d1ff5a57f3a0996dc9c7c8478775ef141105
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/36940
Reviewed-by: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Ben Clayton <bclayton@google.com>
diff --git a/src/writer/hlsl/generator_impl_array_accessor_test.cc b/src/writer/hlsl/generator_impl_array_accessor_test.cc
index fc71b74..3f5dbe3 100644
--- a/src/writer/hlsl/generator_impl_array_accessor_test.cc
+++ b/src/writer/hlsl/generator_impl_array_accessor_test.cc
@@ -33,14 +33,14 @@
   auto* expr = IndexAccessor("ary", 5);
 
   ASSERT_TRUE(gen.EmitExpression(pre, out, expr)) << gen.error();
-  EXPECT_EQ(result(), "ary[5]");
+  EXPECT_EQ(result(), "test_ary[5]");
 }
 
 TEST_F(HlslGeneratorImplTest_Expression, EmitArrayAccessor) {
   auto* expr = IndexAccessor("ary", "idx");
 
   ASSERT_TRUE(gen.EmitExpression(pre, out, expr)) << gen.error();
-  EXPECT_EQ(result(), "ary[idx]");
+  EXPECT_EQ(result(), "test_ary[test_idx]");
 }
 
 }  // namespace