Set referrer for webstore inline install requests, so we can see what the top pages that use it are

chrome/browser/extensions/webstore_inline_installer.cc

Index: chrome/browser/extensions/webstore_inline_installer.cc
diff --git a/chrome/browser/extensions/webstore_inline_installer.cc b/chrome/browser/extensions/webstore_inline_installer.cc
index a3af2c638f2366c9da4c978df3900781a60c1d23..a65936fd96ec7f32766cfdf366422c6d7359c570 100644
--- a/chrome/browser/extensions/webstore_inline_installer.cc
+++ b/chrome/browser/extensions/webstore_inline_installer.cc
@@ -175,6 +175,10 @@ void WebstoreInlineInstaller::BeginInstall() {
       tab_contents()->browser_context());
   webstore_data_url_fetcher_->SetRequestContext(
       profile->GetRequestContext());
+  // Use the requesting page as the referrer both since that is more correct
+  // (it is the page that caused this request to happen) and so that we can
+  // track top sites that trigger inline install requests.
+  webstore_data_url_fetcher_->SetReferrer(requestor_url_.spec());
   webstore_data_url_fetcher_->SetLoadFlags(net::LOAD_DO_NOT_SEND_COOKIES |
                                            net::LOAD_DO_NOT_SAVE_COOKIES |
                                            net::LOAD_DISABLE_CACHE);