[iwyu] Include handles.h less.

src/compilation-cache.h

 // Copyright 2012 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.
 
 #ifndef V8_COMPILATION_CACHE_H_
 #define V8_COMPILATION_CACHE_H_
 
 #include "src/allocation.h"
-#include "src/handles.h"
 #include "src/objects.h"
 
 namespace v8 {
 namespace internal {
 
+template <typename T>
+class Handle;
+
 // The compilation cache consists of several generational sub-caches which uses
 // this class as a base class. A sub-cache contains a compilation cache tables
 // for each generation of the sub-cache. Since the same source code string has
 // different compiled code for scripts and evals, we use separate sub-caches
 // for different compilation modes, to avoid retrieving the wrong result.
 class CompilationSubCache {
  public:
   CompilationSubCache(Isolate* isolate, int generations)
       : isolate_(isolate),
         generations_(generations) {
@@ skipping 208 matching lines @@
   friend class Isolate;
 
   DISALLOW_COPY_AND_ASSIGN(CompilationCache);
 };
 
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILATION_CACHE_H_