Revert of Moving previews code from components/ to chrome/

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 a0375e5f8833c32f8b2d615610ebdcf4e32b4689..bfc31eaa413f45c50099d837c54aab0ec5c4a08c 100644
--- a/chrome/browser/previews/previews_service.cc
+++ b/chrome/browser/previews/previews_service.cc
@@ -4,64 +4,16 @@
 
 #include "chrome/browser/previews/previews_service.h"
 
-#include "base/bind.h"
 #include "base/files/file_path.h"
 #include "base/memory/ptr_util.h"
 #include "base/sequenced_task_runner.h"
 #include "base/threading/sequenced_worker_pool.h"
 #include "chrome/common/chrome_constants.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"
 #include "components/previews/core/previews_opt_out_store_sql.h"
 #include "components/previews/core/previews_ui_service.h"
 #include "content/public/browser/browser_thread.h"
-
-namespace {
-
-// Returns true if previews can be shown for |type|.
-bool IsPreviewsTypeEnabled(previews::PreviewsType type) {
-  switch (type) {
-    case previews::PreviewsType::OFFLINE:
-      return previews::params::IsOfflinePreviewsEnabled();
-    case previews::PreviewsType::NONE:
-    case previews::PreviewsType::LAST:
-      break;
-  }
-  NOTREACHED();
-  return false;
-}
-
-// Returns the version of preview treatment |type|. Defaults to 0 if not
-// specified in field trial config.
-int GetPreviewsTypeVersion(previews::PreviewsType type) {
-  switch (type) {
-    case previews::PreviewsType::OFFLINE:
-      return previews::params::OfflinePreviewsVersion();
-    case previews::PreviewsType::NONE:
-    case previews::PreviewsType::LAST:
-      break;
-  }
-  NOTREACHED();
-  return -1;
-}
-
-// Returns the enabled PreviewsTypes with their version.
-std::unique_ptr<previews::PreviewsTypeList> GetEnabledPreviews() {
-  std::unique_ptr<previews::PreviewsTypeList> enabled_previews(
-      new previews::PreviewsTypeList());
-
-  // Loop across all previews types (relies on sequential enum values).
-  for (int i = static_cast<int>(previews::PreviewsType::NONE) + 1;
-       i < static_cast<int>(previews::PreviewsType::LAST); ++i) {
-    previews::PreviewsType type = static_cast<previews::PreviewsType>(i);
-    if (IsPreviewsTypeEnabled(type))
-      enabled_previews->push_back({type, GetPreviewsTypeVersion(type)});
-  }
-  return enabled_previews;
-}
-
-}  // namespace
 
 PreviewsService::PreviewsService() {
   DCHECK_CURRENTLY_ON(content::BrowserThread::UI);
@@ -87,7 +39,5 @@
       previews_io_data, io_task_runner,
       base::MakeUnique<previews::PreviewsOptOutStoreSQL>(
           io_task_runner, background_task_runner,
-          profile_path.Append(chrome::kPreviewsOptOutDBFilename),
-          GetEnabledPreviews()),
-      base::Bind(&IsPreviewsTypeEnabled));
+          profile_path.Append(chrome::kPreviewsOptOutDBFilename)));
 }