Add chrome_split_dll gyp variable, and duplicate chrome_main_dll target (reland)

chrome/test/gpu/test_support_gpu.gypi

 # Copyright (c) 2012 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.
 
 # This file is meant to be included into targets which run gpu tests.
 {
   'variables': {
      'test_list_out_dir': '<(SHARED_INTERMEDIATE_DIR)/chrome/test/gpu',
      'src_dir': '../../..',
   },
@@ skipping 84 matching lines @@
     ['toolkit_views==1', {
       'dependencies': [
        '<(src_dir)/ui/views/views.gyp:views',
       ],
     }],
     ['OS=="android"', {
       'dependencies!': [
         'chrome',
       ],
       'dependencies': [
-        '<@(chromium_dependencies)',
+        '<@(chromium_browser_dependencies)',
+        '<@(chromium_child_dependencies)',
         'chrome_resources.gyp:packed_resources',
         'chrome_resources.gyp:packed_extra_resources',
       ],
     }],
   ],
 }