Move SourcePosition into separate header file.

tools/gyp/v8.gyp

 # 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:
 #
 #     * 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 1015 matching lines @@
         '../../src/simulator.h',
         '../../src/small-pointer-list.h',
         '../../src/snapshot/natives.h',
         '../../src/snapshot/natives-common.cc',
         '../../src/snapshot/serialize.cc',
         '../../src/snapshot/serialize.h',
         '../../src/snapshot/snapshot.h',
         '../../src/snapshot/snapshot-common.cc',
         '../../src/snapshot/snapshot-source-sink.cc',
         '../../src/snapshot/snapshot-source-sink.h',
+        '../../src/source-position.h',
         '../../src/splay-tree.h',
         '../../src/splay-tree-inl.h',
         '../../src/startup-data-util.cc',
         '../../src/startup-data-util.h',
         '../../src/string-builder.cc',
         '../../src/string-builder.h',
         '../../src/string-search.h',
         '../../src/string-stream.cc',
         '../../src/string-stream.h',
         '../../src/strtod.cc',
@@ skipping 1080 matching lines @@
         }],
         ['want_separate_host_toolset==1', {
           'toolsets': ['host'],
         }, {
           'toolsets': ['target'],
         }],
       ],
     },
   ],
 }