Infrastructure for reading V8's initial snapshot from external files

mojo/apps/js/test/js_to_cpp_unittest.cc

Index: mojo/apps/js/test/js_to_cpp_unittest.cc
diff --git a/mojo/apps/js/test/js_to_cpp_unittest.cc b/mojo/apps/js/test/js_to_cpp_unittest.cc
index 44526a45c045a7a5dfd51e9274a2a06e95eabf78..c7b15906b83c8dcbcb4ebb0ea0fe02fca28c5943 100644
--- a/mojo/apps/js/test/js_to_cpp_unittest.cc
+++ b/mojo/apps/js/test/js_to_cpp_unittest.cc
@@ -19,6 +19,10 @@
 #include "mojo/public/cpp/system/macros.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+#include "gin/public/isolate_holder.h"
+#endif
+
 namespace mojo {
 namespace js {
 
@@ -400,6 +404,9 @@ class JsToCppTest : public testing::Test {
 
     cpp_side->set_js_side(js_side.get());
 
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+    gin::IsolateHolder::LoadV8Snapshot();
+#endif
     gin::IsolateHolder::Initialize(gin::IsolateHolder::kStrictMode,
                                    gin::ArrayBufferAllocator::SharedInstance());
     gin::IsolateHolder instance;