Issue #4692 - Rewrite web request task to avoid engine self-reference

libadblockplus.gyp

 {
   'conditions': [[
     # We don't want to use curl on Windows and Android, skip the check there
     'OS=="win" or OS=="android"',
     {
       'variables': {
         'have_curl': 0
       }
     },
     {
@@ skipping 57 matching lines @@
       'src/JsEngineTransition.h',
       'src/JsError.cpp',
       'src/JsError.h',
       'src/JsValue.cpp',
       'src/Notification.cpp',
       'src/ReferrerMapping.cpp',
       'src/Scheduler.cpp',
       'src/Scheduler.h',
       'src/Utils.cpp',
       'src/Utils.h',
+      'src/Value.h',
       'src/V8Upgrade.h',
       'src/WebRequestJsObject.cpp',
       'src/WebRequestJsObject.h',
       '<(INTERMEDIATE_DIR)/adblockplus.js.cpp'
     ],
     'direct_dependent_settings': {
       'include_dirs': ['include']
     },
     'conditions': [
       ['OS=="android"', {
@@ skipping 122 matching lines @@
       'test/WebRequest.cpp'
     ],
     'msvs_settings': {
       'VCLinkerTool': {
         'SubSystem': '1',   # Console
         'EntryPointSymbol': 'mainCRTStartup',
       },
     },
   }]
 }