Add cross-platform API to get the form factor of the device

ui/base/ui_base_switches.cc

Index: ui/base/ui_base_switches.cc
diff --git a/ui/base/ui_base_switches.cc b/ui/base/ui_base_switches.cc
index a955933e9045aa3afe78d08f0534b375c81d4187..24b7df39b8af643a7df06a47f5eb2db40f374ff0 100644
--- a/ui/base/ui_base_switches.cc
+++ b/ui/base/ui_base_switches.cc
@@ -50,6 +50,9 @@ const char kLocalePak[] = "locale_pak";
 // do not have a user interface.
 const char kNoMessageBox[] = "no-message-box";
 
+// Uses the tablet specific UI components when available
+const char kTabletUI[] = "tablet-ui";

[Alexei Svitkine (slow), 2013/11/01 18:48:27]

This should be ifdef android.

[yao, 2013/11/04 15:56:19]

Done.

+
 // Enables UI changes that make it easier to use with a touchscreen.
 // WARNING: Do not check this flag directly when deciding what UI to draw,
 // instead you must call ui::GetDisplayLayout