Add a field trial to enable out-of-process V8 pac.

chrome/common/chrome_switches.cc

Index: chrome/common/chrome_switches.cc
diff --git a/chrome/common/chrome_switches.cc b/chrome/common/chrome_switches.cc
index e8d60b3417984b37ad068a4a39725d0e22b16660..7445e28b927b6f30c8a3644f9aa5f2c0c09feff8 100644
--- a/chrome/common/chrome_switches.cc
+++ b/chrome/common/chrome_switches.cc
@@ -291,6 +291,9 @@ const char kDisableOfflineAutoReload[]       = "disable-offline-auto-reload";
 const char kDisableOfflineAutoReloadVisibleOnly[] =
     "disable-offline-auto-reload-visible-only";
 
+// Disable out-of-process V8 proxy resolver.
+const char kDisableOutOfProcessPac[] = "disable-out-of-process-pac";
+
 // Disable the setting to prompt the user for their OS account password before
 // revealing plaintext passwords in the password manager.
 const char kDisablePasswordManagerReauthentication[] =