Issue 6063, 6531 - Update V8 to 6.5.254.41, use C++14 and NDK-r16b

common.gypi

 {
   'variables': {
     'component%': 'static_library',
     'visibility%': 'hidden',
     'library%': 'static_library',
   },
 
   'conditions': [
     ['OS=="linux" or OS=="freebsd" or OS=="openbsd" or OS=="solaris" \
        or OS=="netbsd" or OS=="android"', {
       'target_defaults': {
         'cflags': [ '-pthread' ],
         # V8 headers cause a build error on recent gcc.
         # Adding -fpermissive to solve this.
         # See https://issues.adblockplus.org/ticket/4950
         # We might be able to do without after upgrading V8.
-        'cflags_cc': [ '-fno-rtti', '-std=c++11', '-fexceptions', '-fpermissive' ],
+        'cflags_cc': [ '-fno-rtti', '-std=c++14', '-fexceptions', '-fpermissive' ],
         'cflags!': [ '-Werror', ],
         'ldflags': [ '-pthread', ],
       },
     }],
     ['OS=="mac"', {
       'xcode_settings': {
-        'CLANG_CXX_LANGUAGE_STANDARD': 'c++11',
+        'CLANG_CXX_LANGUAGE_STANDARD': 'c++14',
         'CLANG_CXX_LIBRARY': 'libc++',
       },
     }],
   ],
   'target_conditions': [
     ['OS=="android" and not "host" in toolsets', {
       'target_defaults': {
         'cflags!': [
           '-pthread',  # Not fully supported by Android toolchain. Built-in suport of major functions, no need to link with it.
         ],
@@ skipping 11 matching lines @@
       'Release': {}
     },
     'msvs_cygwin_shell': 0,
     'target_conditions': [
       ['_type=="static_library"', {
         'standalone_static_library': 1
       }]
     ]
   }
 }