deps: split v8_monolith target into separate file

Even if we only use v8_monolith build target, other targets
in v8.gyp with possibly outdated file lists are parsed and
could cause build to fail even with --build-v8-with-gn.

PR-URL: nodejs#19201
Reviewed-By: Ali Ijaz Sheikh <ofrobots@google.com>
Reviewed-By: Myles Borins <myles.borins@gmail.com>
Reviewed-By: Matteo Collina <matteo.collina@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>

common.gypi

@@ -27,7 +27,7 @@
 
     # 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.1',
+    'v8_embedder_string': '-node.2',
 
     # Enable disassembler for `--print-code` v8 options
     'v8_enable_disassembler': 1,

deps/v8/gypfiles/v8-monolithic.gyp

@@ -0,0 +1,57 @@
+# Copyright 2018 the V8 project authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'variables': {
+    'v8_code': 1,
+    'v8_random_seed%': 314159265,
+    'v8_vector_stores%': 0,
+    'embed_script%': "",
+    'warmup_script%': "",
+    'v8_extra_library_files%': [],
+    'v8_experimental_extra_library_files%': [],
+    'mksnapshot_exec': '<(PRODUCT_DIR)/<(EXECUTABLE_PREFIX)mksnapshot<(EXECUTABLE_SUFFIX)',
+    'v8_os_page_size%': 0,
+  },
+  'includes': ['toolchain.gypi', 'features.gypi', 'inspector.gypi'],
+  'targets': [
+    {
+      'target_name': 'v8_monolith',
+      'type': 'none',
+      'direct_dependent_settings': {
+        'include_dirs': [
+          '../include/',
+        ],
+      },
+      'actions': [
+        {
+          'action_name': 'build_with_gn',
+          'inputs': [
+            '../tools//node/build_gn.py',
+          ],
+          'outputs': [
+            '<(INTERMEDIATE_DIR)/gn/obj/libv8_monolith.a',
+            '<(INTERMEDIATE_DIR)/gn/args.gn',
+          ],
+          'action': [
+            '../tools//node/build_gn.py',
+            '--mode', '<(CONFIGURATION_NAME)',
+            '--v8_path', '../',
+            '--build_path', '<(INTERMEDIATE_DIR)/gn',
+            '--host_os', '<(host_os)',
+            '--flag', 'v8_promise_internal_field_count=<(v8_promise_internal_field_count)',
+            '--flag', 'target_cpu="<(target_arch)"',
+            '--flag', 'target_os="<(OS)"',
+            '--flag', 'v8_target_cpu="<(v8_target_arch)"',
+            '--flag', 'v8_embedder_string="<(v8_embedder_string)"',
+            '--flag', 'v8_use_snapshot=<(v8_use_snapshot)',
+            '--flag', 'v8_optimized_debug=<(v8_optimized_debug)',
+            '--flag', 'v8_enable_disassembler=<(v8_enable_disassembler)',
+            '--flag', 'v8_postmortem_support=<(v8_postmortem_support)',
+          ],
+        },
+      ],
+    },
+  ],
+}

deps/v8/gypfiles/v8.gyp

@@ -2580,42 +2580,5 @@
         },
       ],
     },
-    {
-      'target_name': 'v8_monolith',
-      'type': 'none',
-      'direct_dependent_settings': {
-        'include_dirs': [
-          '../include/',
-        ],
-      },
-      'actions': [
-        {
-          'action_name': 'build_with_gn',
-          'inputs': [
-            '../tools//node/build_gn.py',
-          ],
-          'outputs': [
-            '<(INTERMEDIATE_DIR)/gn/obj/libv8_monolith.a',
-            '<(INTERMEDIATE_DIR)/gn/args.gn',
-          ],
-          'action': [
-            '../tools//node/build_gn.py',
-            '--mode', '<(CONFIGURATION_NAME)',
-            '--v8_path', '../',
-            '--build_path', '<(INTERMEDIATE_DIR)/gn',
-            '--host_os', '<(host_os)',
-            '--flag', 'v8_promise_internal_field_count=<(v8_promise_internal_field_count)',
-            '--flag', 'target_cpu="<(target_arch)"',
-            '--flag', 'target_os="<(OS)"',
-            '--flag', 'v8_target_cpu="<(v8_target_arch)"',
-            '--flag', 'v8_embedder_string="<(v8_embedder_string)"',
-            '--flag', 'v8_use_snapshot=<(v8_use_snapshot)',
-            '--flag', 'v8_optimized_debug=<(v8_optimized_debug)',
-            '--flag', 'v8_enable_disassembler=<(v8_enable_disassembler)',
-            '--flag', 'v8_postmortem_support=<(v8_postmortem_support)',
-          ],
-        },
-      ],
-    },
   ],
 }

node.gypi

@@ -61,7 +61,7 @@
     [ 'node_use_bundled_v8=="true"', {
       'conditions': [
         [ 'build_v8_with_gn=="true"', {
-          'dependencies': ['deps/v8/gypfiles/v8.gyp:v8_monolith'],
+          'dependencies': ['deps/v8/gypfiles/v8-monolithic.gyp:v8_monolith'],
         }, {
           'dependencies': [
             'deps/v8/gypfiles/v8.gyp:v8',