Add netbsd support to gyp build.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 9129d0170ca3ba1d4ce0cb55d7246f8799013dcc..dab8bf5800375aca6c8ef9ba39ceac61ceb6949f 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -1,4 +1,4 @@
-# Copyright 2011 the V8 project authors. All rights reserved.
+# Copyright 2012 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:
@@ -215,7 +215,8 @@
           },
         },
       }],
-      ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris"', {
+      ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris" \
+         or OS=="netbsd"', {
         'conditions': [
           [ 'target_arch=="ia32"', {
             'cflags': [ '-m32' ],
@@ -259,7 +260,10 @@
           ['OS=="freebsd" or OS=="openbsd"', {
             'cflags': [ '-I/usr/local/include' ],
           }],
-          ['OS=="linux" or OS=="freebsd" or OS=="openbsd"', {
+          ['OS=="netbsd"', {
+            'cflags': [ '-I/usr/pkg/include -Wno-strict-aliasing' ],
+          }],
+          ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="netbsd"', {
             'cflags': [ '-Wall', '<(werror)', '-W', '-Wno-unused-parameter',
                         '-Wnon-virtual-dtor' ],
           }],
@@ -267,7 +271,7 @@
       },
       'Release': {
         'conditions': [
-          ['OS=="linux" or OS=="freebsd" or OS=="openbsd"', {
+          ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="netbsd"', {
             'cflags!': [
               '-O2',
               '-Os',
@@ -290,6 +294,9 @@
           ['OS=="freebsd" or OS=="openbsd"', {
             'cflags': [ '-I/usr/local/include' ],
           }],
+          ['OS=="netbsd"', {
+            'cflags': [ '-I/usr/pkg/include -Wno-strict-aliasing' ],
+          }],
           ['OS=="mac"', {
             'xcode_settings': {
               'GCC_OPTIMIZATION_LEVEL': '3',  # -O3