Add copyright headers to remaining gyp files.

gyp/tools.gyp

+# Copyright 2015 Google Inc.
+#
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
     # GYP file to build various tools.
 #
 # To build on Linux:
 #  ./gyp_skia tools.gyp && make tools
 #
 {
   'includes': [
     'apptype_console.gypi',
   ],
   'targets': [
@@ skipping 755 matching lines @@
               'flags.gyp:flags',
               'skia_lib.gyp:skia_lib',
               'resources',
             ],
           },
         ],
       },
     ],
   ],
 }