Pepper and WebKit API change to support a plugin knowing if a scrollbar is an overlay one.

ppapi/ppapi_cpp.gypi

 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 {
   'targets': [
     {
       'target_name': 'ppapi_c<(nacl_ppapi_library_suffix)',
       'type': 'none',
       'all_dependent_settings': {
@@ skipping 52 matching lines @@
         'c/dev/ppb_file_chooser_dev.h',
         'c/dev/ppb_find_dev.h',
         'c/dev/ppb_font_dev.h',
         'c/dev/ppb_fullscreen_dev.h',
         'c/dev/ppb_graphics_3d_dev.h',
         'c/dev/ppb_graphics_3d_trusted_dev.h',
         'c/dev/ppb_memory_dev.h',
         'c/dev/ppb_opengles_dev.h',
         'c/dev/ppb_query_policy_dev.h',
         'c/dev/ppb_scrollbar_dev.h',
+        'c/dev/ppb_scrollbar_group_dev.h',
         'c/dev/ppb_surface_3d_dev.h',
         'c/dev/ppb_testing_dev.h',
         'c/dev/ppb_url_util_dev.h',
         'c/dev/ppb_video_decoder_dev.h',
         'c/dev/ppb_widget_dev.h',
         'c/dev/ppb_zoom_dev.h',
         'c/dev/ppp_cursor_control_dev.h',
         'c/dev/ppp_find_dev.h',
         'c/dev/ppp_graphics_3d_dev.h',
         'c/dev/ppp_network_state_dev.h',
@@ skipping 116 matching lines @@
         'cpp/dev/graphics_3d_client_dev.cc',
         'cpp/dev/graphics_3d_client_dev.h',
         'cpp/dev/graphics_3d_dev.cc',
         'cpp/dev/graphics_3d_dev.h',
         'cpp/dev/memory_dev.cc',
         'cpp/dev/memory_dev.h',
         'cpp/dev/printing_dev.cc',
         'cpp/dev/printing_dev.h',
         'cpp/dev/scrollbar_dev.cc',
         'cpp/dev/scrollbar_dev.h',
+        'cpp/dev/scrollbar_group_dev.cc',
+        'cpp/dev/scrollbar_group_dev.h',
         'cpp/dev/selection_dev.cc',
         'cpp/dev/selection_dev.h',
         'cpp/dev/surface_3d_dev.cc',
         'cpp/dev/surface_3d_dev.h',
         'cpp/dev/url_util_dev.cc',
         'cpp/dev/url_util_dev.h',
         'cpp/dev/video_decoder_client_dev.cc',
         'cpp/dev/video_decoder_client_dev.h',
         'cpp/dev/video_decoder_dev.cc',
         'cpp/dev/video_decoder_dev.h',
@@ skipping 58 matching lines @@
         }],
         ['OS=="mac"', {
           'xcode_settings': {
             'WARNING_CFLAGS': ['-Wextra', '-pedantic'],
            },
         }]
       ],
     },
   ],
 }