Realize IWYU pattern for handles.h header.

src/execution.h

 // Copyright 2014 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_EXECUTION_H_
 #define V8_EXECUTION_H_
 
+#include "src/allocation.h"
+#include "src/base/atomicops.h"
 #include "src/handles.h"
+#include "src/utils.h"
 
 namespace v8 {
 namespace internal {
 
+// Forward declarations.
+class JSRegExp;
+
 class Execution final : public AllStatic {
  public:
   // Call a function, the caller supplies a receiver and an array
   // of arguments. Arguments are Object* type. After function returns,
   // pointers in 'args' might be invalid.
   //
   // *pending_exception tells whether the invoke resulted in
   // a pending exception.
   //
   // When convert_receiver is set, and the receiver is not an object,
@@ skipping 260 matching lines @@
   friend class Isolate;
   friend class StackLimitCheck;
   friend class PostponeInterruptsScope;
 
   DISALLOW_COPY_AND_ASSIGN(StackGuard);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_EXECUTION_H_