Include what you use for the files zone*

src/zone.h

 // Copyright 2011 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 10 matching lines @@
 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 // 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_ZONE_H_
 #define V8_ZONE_H_
 
+#include <stddef.h>

[Kevin Millikin (Chromium), 2012/01/30 09:25:45]

globals.h includes ../include/v8stdint.h, which includes <stddef.h>.  I think
it's safe to rely on that, otherwise we would be including <stddef.h> (for NULL)
in almost every single file.

Suggestion: remove this line, "globals.h" is enough.

+
 #include "allocation.h"
+#include "checks.h"
+#include "globals.h"
+#include "list.h"
+#include "splay-tree.h"
 
 namespace v8 {
 namespace internal {
 
 
 // Zone scopes are in one of two modes.  Either they delete the zone
 // on exit or they do not.
 enum ZoneScopeMode {
   DELETE_ON_EXIT,
   DONT_DELETE_ON_EXIT
 };
 
 class Segment;
+class Isolate;
 
 // The Zone supports very fast allocation of small chunks of
 // memory. The chunks cannot be deallocated individually, but instead
 // the Zone supports deallocating all chunks in one fast
 // operation. The Zone is used to hold temporary data structures like
 // the abstract syntax tree, which is deallocated after compilation.
 
 // Note: There is no need to initialize the Zone; the first time an
 // allocation is attempted, a segment of memory will be requested
 // through a call to malloc().
@@ skipping 184 matching lines @@
  public:
   ZoneSplayTree()
       : SplayTree<Config, ZoneListAllocationPolicy>() {}
   ~ZoneSplayTree();
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_ZONE_H_