Infrastructure for reading V8's initial snapshot from external files

net/proxy/proxy_resolver_v8.cc

Index: net/proxy/proxy_resolver_v8.cc
diff --git a/net/proxy/proxy_resolver_v8.cc b/net/proxy/proxy_resolver_v8.cc
index 37f31bfddd9aef4711e0164eee003a92d65edd72..c47a10be2142b84e5e0ce9247d01a0c2f4390ae7 100644
--- a/net/proxy/proxy_resolver_v8.cc
+++ b/net/proxy/proxy_resolver_v8.cc
@@ -26,6 +26,10 @@
 #include "url/url_canon.h"
 #include "v8/include/v8.h"
 
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+#include "gin/public/isolate_holder.h"
+#endif
+
 // Notes on the javascript environment:
 //
 // For the majority of the PAC utility functions, we use the same code
@@ -769,6 +773,11 @@ int ProxyResolverV8::SetPacScript(
 void ProxyResolverV8::EnsureIsolateCreated() {
   if (g_proxy_resolver_isolate_)
     return;
+
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+  gin::IsolateHolder::LoadV8Snapshot();
+#endif
+
   gin::IsolateHolder::Initialize(gin::IsolateHolder::kNonStrictMode,
                                  gin::ArrayBufferAllocator::SharedInstance());
   g_proxy_resolver_isolate_ = new gin::IsolateHolder;