Moved logic for mapping child process FDs for ICU and V8 into child_process_launcher.cc

gin/v8_initializer.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef GIN_V8_INITIALIZER_H_
 #define GIN_V8_INITIALIZER_H_
 
 #include "base/files/file.h"
+#include "base/files/memory_mapped_file.h"
 #include "gin/array_buffer.h"
 #include "gin/gin_export.h"
 #include "gin/public/isolate_holder.h"
 #include "gin/public/v8_platform.h"
 #include "v8/include/v8.h"
 
 namespace gin {
 
 class GIN_EXPORT V8Initializer {
  public:
@@ skipping 24 matching lines @@
                                   int64 natives_offset,
                                   int64 natives_size);
 
   // Load V8 snapshot from default resources, if they are available.
   static void LoadV8Snapshot();
 
   // Load V8 natives source from default resources. Contains asserts
   // so that it will not return if natives cannot be loaded.
   static void LoadV8Natives();
 
-  // Opens the V8 snapshot data files and returns open file descriptors to these
-  // files in |natives_fd_out| and |snapshot_fd_out|, which can be passed to
-  // child processes.
-  static bool OpenV8FilesForChildProcesses(base::PlatformFile* natives_fd_out,
-                                           base::PlatformFile* snapshot_fd_out)
-      WARN_UNUSED_RESULT;
+  // Opens (unless already cached) and returns the V8 natives file.
+  // Use with LoadV8NativesFromFD().
+  // Asserts if the file does not exist.
+  static base::PlatformFile GetOpenNativesFileForChildProcesses(
+      base::MemoryMappedFile::Region* region_out);
+
+  // Opens (unless already cached) and returns the V8 snapshot file.
+  // Use with LoadV8SnapshotFromFD().
+  // Will return -1 if the file does not exist.
+  static base::PlatformFile GetOpenSnapshotFileForChildProcesses(
+      base::MemoryMappedFile::Region* region_out);
 #endif  // V8_USE_EXTERNAL_STARTUP_DATA
 };
 
 }  // namespace gin
 
 #endif  // GIN_V8_INITIALIZER_H_