[MD Bookmarks] Add skeleton for Material Design Bookmarks

chrome/browser/extensions/component_loader.cc

Index: chrome/browser/extensions/component_loader.cc
diff --git a/chrome/browser/extensions/component_loader.cc b/chrome/browser/extensions/component_loader.cc
index 7566a1fa3aca08b5ae6b0037fb71229602a2b088..d149b36999017cce4da1b5d34f4696502586870b 100644
--- a/chrome/browser/extensions/component_loader.cc
+++ b/chrome/browser/extensions/component_loader.cc
@@ -22,6 +22,7 @@
 #include "chrome/browser/search/hotword_service.h"
 #include "chrome/browser/search/hotword_service_factory.h"
 #include "chrome/common/channel_info.h"
+#include "chrome/common/chrome_features.h"
 #include "chrome/common/chrome_paths.h"
 #include "chrome/common/chrome_switches.h"
 #include "chrome/common/extensions/extension_constants.h"
@@ -106,6 +107,10 @@ bool IsNormalSession() {
 }
 #endif  // defined(OS_CHROMEOS)
 
+bool IsMaterialDesignBookmarksEnabled() {
+  return base::FeatureList::IsEnabled(features::kMaterialDesignBookmarks);
+}
+
 }  // namespace
 
 ComponentLoader::ComponentExtensionInfo::ComponentExtensionInfo(
@@ -454,6 +459,13 @@ void ComponentLoader::EnableBackgroundExtensionsForTesting() {
 
 void ComponentLoader::AddDefaultComponentExtensions(
     bool skip_session_components) {
+  base::FilePath bookmarks_path(IsMaterialDesignBookmarksEnabled()
+                                    ? FILE_PATH_LITERAL("md_bookmarks")
+                                    : FILE_PATH_LITERAL("bookmark_manager"));
+  int bookmark_manifest_id = IsMaterialDesignBookmarksEnabled()

[Dan Beam, 2016/10/25 18:05:51]

can we cache this result?

also, can we just do the feature enabledness check in this method only?

why do we need another method in an anonymous namespace?

[calamity, 2016/10/28 05:58:22]

Done.

+                                 ? IDR_MD_BOOKMARKS_MANIFEST
+                                 : IDR_BOOKMARKS_MANIFEST;
+
   // Do not add component extensions that have background pages here -- add them
   // to AddDefaultComponentExtensionsWithBackgroundPages.
 #if defined(OS_CHROMEOS)
@@ -472,16 +484,14 @@ void ComponentLoader::AddDefaultComponentExtensions(
     const base::CommandLine* command_line =
         base::CommandLine::ForCurrentProcess();
     if (!command_line->HasSwitch(chromeos::switches::kGuestSession))
-      Add(IDR_BOOKMARKS_MANIFEST,
-          base::FilePath(FILE_PATH_LITERAL("bookmark_manager")));
+      Add(bookmark_manifest_id, bookmarks_path);
 
     Add(IDR_CROSH_BUILTIN_MANIFEST, base::FilePath(FILE_PATH_LITERAL(
         "/usr/share/chromeos-assets/crosh_builtin")));
   }
 #else  // defined(OS_CHROMEOS)
   DCHECK(!skip_session_components);
-  Add(IDR_BOOKMARKS_MANIFEST,
-      base::FilePath(FILE_PATH_LITERAL("bookmark_manager")));
+  Add(bookmark_manifest_id, bookmarks_path);
 #if defined(ENABLE_PRINTING)
   // Cloud Print component app. Not required on Chrome OS.
   Add(IDR_CLOUDPRINT_MANIFEST,