Support landscape layouts.

Add support for landscape layouts to the existing portrait support.

Bug: http://b/29418855
Test: tested manually with "Run graphics test" on flounder/fugu/ryu.
Change-Id: Ib4a62bf5f2b8a1cef6028a01f05145104660560a
diff --git a/screen_ui.h b/screen_ui.h
index 4319b76..8987757 100644
--- a/screen_ui.h
+++ b/screen_ui.h
@@ -77,8 +77,8 @@
 
     // The scale factor from dp to pixels. 1.0 for mdpi, 4.0 for xxxhdpi.
     float density_;
-    // True if we should use the large layout.
-    bool is_large_;
+    // The layout to use.
+    int layout_;
 
     GRSurface* error_icon;