fix: don't export private V8 symbols that can cause native node modul…

…es to crash (#18281)

patches/common/v8/.patches

@@ -5,3 +5,4 @@ deps_provide_more_v8_backwards_compatibility.patch
 dcheck.patch
 export_symbols_needed_for_windows_build.patch
 workaround_an_undefined_symbol_error.patch
+do_not_export_private_v8_symbols_on_windows.patch

patches/common/v8/do_not_export_private_v8_symbols_on_windows.patch

@@ -0,0 +1,52 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: Tomas Rycl <torycl@microsoft.com>
+Date: Mon, 13 May 2019 15:48:48 +0200
+Subject: Do not export private V8 symbols on Windows
+
+This change stops private V8 symbols and internal crt methods being exported.
+It fixes an issue where native node modules can import
+incorrect CRT methods and crash on Windows.
+It also reduces size of node.lib by 75%.
+
+This patch can be safely removed if, when it is removed, `node.lib` does not
+contain any standard C++ library exports (e.g. `std::ostringstream`).
+
+diff --git a/BUILD.gn b/BUILD.gn
+index 1acc7006545bd4ff6112b444758bde4c16d0c3e5..748d700cead149f5cdeebcfe11d07516db3d6a86 100644
+--- a/BUILD.gn
++++ b/BUILD.gn
+@@ -269,6 +269,10 @@ config("internal_config") {
+     ":v8_header_features",
+   ]
+
++  if (!is_component_build && is_electron_build) {
++    defines += [ "HIDE_PRIVATE_SYMBOLS" ]
++  }
++
+   if (is_component_build || is_electron_build) {
+     defines += [ "BUILDING_V8_SHARED" ]
+   }
+diff --git a/src/base/macros.h b/src/base/macros.h
+index ad70e9820ddb4a63639ca7738c1836cb87766db5..d40be9b57294583f74594d88d9b7d7b937b2db3c 100644
+--- a/src/base/macros.h
++++ b/src/base/macros.h
+@@ -414,13 +414,17 @@ bool is_inbounds(float_t v) {
+ #ifdef V8_OS_WIN
+
+ // Setup for Windows shared library export.
++#if defined(HIDE_PRIVATE_SYMBOLS)
++#define V8_EXPORT_PRIVATE
++#else //if !defined(HIDE_PRIVATE_SYMBOLS)
+ #ifdef BUILDING_V8_SHARED
+ #define V8_EXPORT_PRIVATE __declspec(dllexport)
+ #elif USING_V8_SHARED
+ #define V8_EXPORT_PRIVATE __declspec(dllimport)
+-#else
++#else //!(BUILDING_V8_SHARED || USING_V8_SHARED)
+ #define V8_EXPORT_PRIVATE
+-#endif  // BUILDING_V8_SHARED
++#endif
++#endif
+
+ #else  // V8_OS_WIN
+