Improve process launch handle sharing API.

chrome/utility/importer/firefox_importer_unittest_utils_mac.cc

Index: chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
diff --git a/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc b/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
index 53f3a7718d8bd6ad8e82231b253ce8cad5249fcd..cff0a8cfe8f321b18c65ede9465e1840ad25b936 100644
--- a/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
+++ b/chrome/utility/importer/firefox_importer_unittest_utils_mac.cc
@@ -55,13 +55,10 @@ base::Process LaunchNSSDecrypterChildProcess(
   // why we need this.
   base::LaunchOptions options;
   options.environ["DYLD_FALLBACK_LIBRARY_PATH"] = nss_path.value();
-
-  base::FileHandleMappingVector fds_to_map;
-  fds_to_map.push_back(std::pair<int, int>(
+  options.fds_to_remap.push_back(std::pair<int, int>(
       mojo_handle.get().handle,
       kMojoIPCChannel + base::GlobalDescriptors::kBaseDescriptor));
 
-  options.fds_to_remap = &fds_to_map;
   return base::LaunchProcess(cl.argv(), options);
 }