Enable ASSERT when DCHECK_ALWAYS_ON is defined.

Source/web/web.gyp

 #
 # Copyright (C) 2011 Google Inc. 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
@@ skipping 14 matching lines @@
 # DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 # THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 #
 
 {
     'includes': [
         '../bindings/bindings.gypi',
         '../core/core.gypi',
+        '../build/defines_from_chromium.gypi',
         '../build/features.gypi',
         '../build/scripts/scripts.gypi',
         '../build/win/precompile.gypi',
         '../modules/modules.gypi',
         '../wtf/wtf.gypi',
         'web.gypi',
     ],
     'targets': [
         {
             'target_name': 'webkit',
@@ skipping 332 matching lines @@
         ['clang==1', {
             'target_defaults': {
                 'cflags': ['-Wglobal-constructors'],
                 'xcode_settings': {
                     'WARNING_CFLAGS': ['-Wglobal-constructors'],
                 },
             },
         }],
     ], # conditions
 }