Add support to previews/ for Server LoFi and LitePages

chrome/browser/previews/previews_service.cc

Index: chrome/browser/previews/previews_service.cc
diff --git a/chrome/browser/previews/previews_service.cc b/chrome/browser/previews/previews_service.cc
index 8ddcfd18ca285b87f1c1733f6bb92f6b5b9896d2..5b28fabc51db1af8bed8b3e32b1a719cd993ec8f 100644
--- a/chrome/browser/previews/previews_service.cc
+++ b/chrome/browser/previews/previews_service.cc
@@ -10,6 +10,7 @@
 #include "base/sequenced_task_runner.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "chrome/common/chrome_constants.h"
+#include "components/data_reduction_proxy/core/common/data_reduction_proxy_params.h"
 #include "components/previews/core/previews_experiments.h"
 #include "components/previews/core/previews_io_data.h"
 #include "components/previews/core/previews_opt_out_store.h"
@@ -26,6 +27,14 @@ bool IsPreviewsTypeEnabled(previews::PreviewsType type) {
       return previews::params::IsOfflinePreviewsEnabled();
     case previews::PreviewsType::CLIENT_LOFI:
       return previews::params::IsClientLoFiEnabled();
+    case previews::PreviewsType::SERVER_LOFI:
+      return data_reduction_proxy::params::IsLoFiOnViaFlags() ||
+             data_reduction_proxy::params::IsIncludedInLoFiEnabledFieldTrial();
+    case previews::PreviewsType::LITE_PAGE:
+      return (data_reduction_proxy::params::IsLoFiOnViaFlags() &&
+              data_reduction_proxy::params::AreLitePagesEnabledViaFlags()) ||
+             data_reduction_proxy::params::IsIncludedInLitePageFieldTrial();
+    // List remaining enum cases vs. default to catch when new one is added.

[tbansal1, 2017/05/02 21:49:30]

nit: I do not think this comment is needed since it is pretty common pattern in
switch case (probably it's also a part of the style guide).

[RyanSturm, 2017/05/02 22:57:18]

Done.

     case previews::PreviewsType::NONE:
     case previews::PreviewsType::LAST:
       break;
@@ -42,6 +51,11 @@ int GetPreviewsTypeVersion(previews::PreviewsType type) {
       return previews::params::OfflinePreviewsVersion();
     case previews::PreviewsType::CLIENT_LOFI:
       return previews::params::ClientLoFiVersion();
+    case previews::PreviewsType::LITE_PAGE:
+      return data_reduction_proxy::params::LitePageVersion();
+    case previews::PreviewsType::SERVER_LOFI:
+      return data_reduction_proxy::params::LoFiVersion();
+    // List remaining enum cases vs. default to catch when new one is added.
     case previews::PreviewsType::NONE:
     case previews::PreviewsType::LAST:
       break;