Add a command line option and a Finch experiment for script streaming.

chrome/browser/chrome_browser_field_trials.cc

Index: chrome/browser/chrome_browser_field_trials.cc
diff --git a/chrome/browser/chrome_browser_field_trials.cc b/chrome/browser/chrome_browser_field_trials.cc
index 396aef6ee8108d01b4740a2e975004cd8c99eff5..4f25b2f61b5327e0c96b089ae950246a2376b266 100644
--- a/chrome/browser/chrome_browser_field_trials.cc
+++ b/chrome/browser/chrome_browser_field_trials.cc
@@ -61,6 +61,7 @@ void ChromeBrowserFieldTrials::InstantiateDynamicTrials() {
   base::FieldTrialList::FindValue("MouseEventPreconnect");
   base::FieldTrialList::FindValue("UnauthorizedPluginInfoBar");
   base::FieldTrialList::FindValue("DisplayList2dCanvas");
+  base::FieldTrialList::FindValue("V8ScriptStreaming");
   // Activate the autocomplete dynamic field trials.
   OmniboxFieldTrial::ActivateDynamicTrials();
 }