Add about flag for server lite page previews

Bug: 864187
Change-Id: I63d1b7e6cab53bb34bcd078218b2588eeaa56a29
Reviewed-on: https://chromium-review.googlesource.com/c/1269835
Reviewed-by: Ryan Sturm <[email protected]>
Commit-Queue: Robert Ogden <[email protected]>
Cr-Commit-Position: refs/heads/master@{#597721}
diff --git a/chrome/browser/flag_descriptions.cc b/chrome/browser/flag_descriptions.cc
index ea84174..4f997fb 100644
--- a/chrome/browser/flag_descriptions.cc
+++ b/chrome/browser/flag_descriptions.cc
@@ -558,6 +558,13 @@
     "Enable showing the Previews UI in the Omnibox on Android instead of an "
     "InfoBar. This has no effect on other platforms.";
 
+const char kEnableLitePageServerPreviewsName[] = "Lite Page Server Previews";
+const char kEnableLitePageServerPreviewsDescription[] =
+    "Enable showing Lite Page Previews served from the Chrome Data Proxy "
+    "service. This feature will cause Chrome to redirect eligible navigations "
+    "to a Google-owned domain that serves a pre-rendered version of the "
+    "original page.";
+
 const char kEnableHttpFormWarningName[] =
     "Show in-form warnings for sensitive fields when the top-level page is not "
     "HTTPS";