build: fix missing symbol error in debug build

Link in a dummy BuiltinCanAllocate, otherwise the link step fails with a
missing symbol error in debug builds.

Signed-off-by: Ben Noordhuis <info@bnoordhuis.nl>

Author: bnoordhuis

tools/v8_gypfiles/v8.gyp

@@ -383,6 +383,7 @@
       'toolsets': ['target'],
       'sources': [
         '<(V8_ROOT)/src/init/setup-isolate-deserialize.cc',
+        '<(V8_ROOT)/src/snapshot/builtins-effects-dummy.cc',
       ],
       'xcode_settings': {
         # V8 7.4 over macOS10.11 compatibility