Reland of "Added common layout framework for system menu rows."

ash/BUILD.gn

Index: ash/BUILD.gn
diff --git a/ash/BUILD.gn b/ash/BUILD.gn
index a907e6704cadd22de7bdd6635d3cf77628b14374..5e4598282e9bcc42d69747fbf06b31c268cc3896 100644
--- a/ash/BUILD.gn
+++ b/ash/BUILD.gn
@@ -354,6 +354,8 @@ component("ash") {
     "common/system/tray/ime_info.h",
     "common/system/tray/label_tray_view.cc",
     "common/system/tray/label_tray_view.h",
+    "common/system/tray/size_range_layout.cc",
+    "common/system/tray/size_range_layout.h",
     "common/system/tray/special_popup_row.cc",
     "common/system/tray/special_popup_row.h",
     "common/system/tray/system_menu_button.cc",
@@ -400,8 +402,12 @@ component("ash") {
     "common/system/tray/tray_popup_label_button.h",
     "common/system/tray/tray_popup_label_button_border.cc",
     "common/system/tray/tray_popup_label_button_border.h",
+    "common/system/tray/tray_popup_layout_factory.cc",
+    "common/system/tray/tray_popup_layout_factory.h",
     "common/system/tray/tray_utils.cc",
     "common/system/tray/tray_utils.h",
+    "common/system/tray/tri_view.cc",
+    "common/system/tray/tri_view.h",
     "common/system/tray/view_click_listener.h",
     "common/system/tray_accessibility.cc",
     "common/system/tray_accessibility.h",
@@ -1221,8 +1227,10 @@ test("ash_unittests") {
     "common/system/chromeos/session/tray_session_length_limit_unittest.cc",
     "common/system/ime/tray_ime_chromeos_unittest.cc",
     "common/system/tiles/tray_tiles_unittest.cc",
+    "common/system/tray/size_range_layout_unittest.cc",
     "common/system/tray/system_tray_unittest.cc",
     "common/system/tray/tray_details_view_unittest.cc",
+    "common/system/tray/tri_view_unittest.cc",
     "common/system/user/tray_user_unittest.cc",
 
     # TODO: convert to use AshTest http://crbug.com/654517.