deps,v8: silence V8 self-deprecation warnings

Author: refack

common.gypi

@@ -38,19 +38,20 @@
 
     # Reset this number to 0 on major V8 upgrades.
     # Increment by one for each non-official patch applied to deps/v8.
-    'v8_embedder_string': '-node.8',
+    'v8_embedder_string': '-node.9',
 
     ##### V8 defaults for Node.js #####
 
     # Old time default, now explicitly stated.
     'v8_use_snapshot': 'true',
 
+    # These are more relevant for V8 internal development.
     # Refs: https://github.com/nodejs/node/issues/23122
     # Refs: https://github.com/nodejs/node/issues/23167
-    # Enable compiler warnings when using V8_DEPRECATED apis.
-    'v8_deprecation_warnings': 1,
-    # Enable compiler warnings when using V8_DEPRECATE_SOON apis.
-    'v8_imminent_deprecation_warnings': 1,
+    # Enable compiler warnings when using V8_DEPRECATED apis from V8 code.
+    'v8_deprecation_warnings': 0,
+    # Enable compiler warnings when using V8_DEPRECATE_SOON apis from V8 code.
+    'v8_imminent_deprecation_warnings': 0,
 
     # Enable disassembler for `--print-code` v8 options
     'v8_enable_disassembler': 1,

deps/v8/gypfiles/features.gypi

@@ -164,9 +164,13 @@
       }],
       ['v8_deprecation_warnings==1', {
         'defines': ['V8_DEPRECATION_WARNINGS',],
+      },{
+        'defines!': ['V8_DEPRECATION_WARNINGS',],
       }],
       ['v8_imminent_deprecation_warnings==1', {
         'defines': ['V8_IMMINENT_DEPRECATION_WARNINGS',],
+      },{
+        'defines!': ['V8_IMMINENT_DEPRECATION_WARNINGS',],
       }],
       ['v8_enable_i18n_support==1', {
         'defines': ['V8_INTL_SUPPORT',],