Infrastructure for reading V8's initial snapshot from external files

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index e6556154ee1bca31f7a0adcc65a8c7172a3ae66b..215c20bf1937e760d54b0e7913956000e06d8a08 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -2449,6 +2449,26 @@ void ChromeContentBrowserClient::GetAdditionalMappedFilesForChildProcess(
   mappings->push_back(FileDescriptorInfo(kAndroidICUDataDescriptor,
                                          FileDescriptor(icudata_file.Pass())));
 
+#ifdef V8_USE_EXTERNAL_STARTUP_DATA
+  base::FilePath v8_data_path;
+  PathService::Get(base::DIR_ANDROID_APP_DATA, &v8_data_path);
+  DCHECK(!v8_data_path.empty());
+
+  int file_flags = base::File::FLAG_OPEN | base::File::FLAG_READ;
+  base::FilePath v8_natives_data_path =
+      v8_data_path.AppendASCII("natives_blob.bin");
+  base::FilePath v8_snapshot_data_path =
+      v8_data_path.AppendASCII("snapshot_blob.bin");
+  base::File v8_natives_data_file(v8_natives_data_path, file_flags);
+  base::File v8_snapshot_data_file(v8_snapshot_data_path, file_flags);
+  DCHECK(v8_natives_data_file.IsValid());
+  DCHECK(v8_snapshot_data_file.IsValid());
+  mappings->push_back(FileDescriptorInfo(kV8NativesDataDescriptor,
+      FileDescriptor(v8_natives_data_file.Pass())));
+  mappings->push_back(FileDescriptorInfo(kV8SnapshotDataDescriptor,
+      FileDescriptor(v8_snapshot_data_file.Pass())));
+#endif  // V8_USE_EXTERNAL_STARTUP_DATA
+
 #else
   int crash_signal_fd = GetCrashSignalFD(command_line);
   if (crash_signal_fd >= 0) {