Rename media gallery -> media galleries in pref/UI components.

chrome/common/pref_names.cc

Index: chrome/common/pref_names.cc
diff --git a/chrome/common/pref_names.cc b/chrome/common/pref_names.cc
index a44dcb475944ab63e6f5625ec2d3fd380434bd09..463ff502fe52832d26e09117fb6ae7a7aac710e2 100644
--- a/chrome/common/pref_names.cc
+++ b/chrome/common/pref_names.cc
@@ -1928,12 +1928,12 @@ const char kComponentUpdaterState[] = "component_updater.state";
 const char kWebIntentsEnabled[] = "webintents.enabled";
 
 // The next media gallery ID to assign.
-const char kMediaGalleryUniqueId[] = "media_gallery.gallery_id";
+const char kMediaGalleriesUniqueId[] = "media_galleries.gallery_id";
 
 // A list of dictionaries, where each dictionary represents a known media
 // gallery.
-const char kMediaGalleryRememberedGalleries[] =
-    "media_gallery.remembered_galleries";
+const char kMediaGalleriesRememberedGalleries[] =
+    "media_galleries.remembered_galleries";
 
 #if defined(USE_AURA)
 // String value corresponding to ash::Shell::ShelfAlignment.