Infrastructure for reading V8's initial snapshot from external files

content/app/content_main_runner.cc

Index: content/app/content_main_runner.cc
diff --git a/content/app/content_main_runner.cc b/content/app/content_main_runner.cc
index 32dd24ef38cab7b06c639924cb01075f7c09edad..ed409c48ab68fd6543e5137ab8b08a52fe793414 100644
--- a/content/app/content_main_runner.cc
+++ b/content/app/content_main_runner.cc
@@ -43,6 +43,9 @@
 #include "content/renderer/in_process_renderer_thread.h"
 #include "content/utility/in_process_utility_thread.h"
 #include "crypto/nss_util.h"
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+#include "gin/public/isolate_holder.h"
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
 #include "ipc/ipc_descriptors.h"
 #include "ipc/ipc_switches.h"
 #include "media/base/media.h"
@@ -715,9 +718,25 @@ class ContentMainRunnerImpl : public ContentMainRunner {
       CHECK(base::i18n::InitializeICUWithFileDescriptor(icudata_fd));
     else
       CHECK(base::i18n::InitializeICU());
+
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+    int v8_natives_fd = base::GlobalDescriptors::GetInstance()->MaybeGet(
+        kV8NativesDataDescriptor);
+    int v8_snapshot_fd = base::GlobalDescriptors::GetInstance()->MaybeGet(
+        kV8SnapshotDataDescriptor);
+    if (v8_natives_fd != -1 && v8_snapshot_fd != -1)
+      CHECK(gin::IsolateHolder::LoadV8SnapshotFD(v8_natives_fd,
+                                                 v8_snapshot_fd));
+    else
+      CHECK(gin::IsolateHolder::LoadV8Snapshot());
+#endif // V8_USE_EXTERNAL_STARTUP_DATA
+
 #else
     CHECK(base::i18n::InitializeICU());
-#endif
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+    CHECK(gin::IsolateHolder::LoadV8Snapshot());
+#endif // V8_USE_EXTERNAL_STARTUP_DATA
+#endif // OS_ANDROID
 
     InitializeStatsTable(command_line);