Various IWYU fixes.

test/cctest/interpreter/test-interpreter.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <tuple>
 
 #include "src/v8.h"
 
 #include "src/execution.h"
 #include "src/handles.h"
 #include "src/interpreter/bytecode-array-builder.h"
 #include "src/interpreter/bytecode-array-iterator.h"
 #include "src/interpreter/bytecode-label.h"
 #include "src/interpreter/interpreter.h"
+#include "src/unicode-cache.h"
 #include "test/cctest/cctest.h"
 #include "test/cctest/interpreter/interpreter-tester.h"
 #include "test/cctest/test-feedback-vector.h"
 
 namespace v8 {
 namespace internal {
 namespace interpreter {
 
 
 TEST(InterpreterReturn) {
@@ skipping 4802 matching lines @@
     auto callable = tester.GetCallable<>();
 
     Handle<i::Object> return_value = callable().ToHandleChecked();
     CHECK(return_value->SameValue(*tests[i].second));
   }
 }
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8