Small simplification of #include dependencies.

src/jsregexp.h

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 11 matching lines @@
 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 #ifndef V8_JSREGEXP_H_
 #define V8_JSREGEXP_H_
 
 #include "macro-assembler.h"
+#include "zone.h"
 
 namespace v8 {
 namespace internal {
 
 
 class RegExpMacroAssembler;
 
 
 class RegExpImpl {
  public:
@@ skipping 1388 matching lines @@
   int offsets_vector_length_;
   static int static_offsets_vector_[kStaticOffsetsVectorSize];
 
   friend class ExternalReference;
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_JSREGEXP_H_