Add test case for updating the bounds of snapped window.

ash/wm/window_util.h

Index: ash/wm/window_util.h
diff --git a/ash/wm/window_util.h b/ash/wm/window_util.h
index fd77505c40065f38c76bb888d5aa7414abb2f40d..e2322ca68887cc2ae1ffbd51ef5ed1a19b3d5bd5 100644
--- a/ash/wm/window_util.h
+++ b/ash/wm/window_util.h
@@ -15,6 +15,7 @@ class Window;
 
 namespace gfx {
 class Rect;
+class Size;
 }
 
 namespace ui {
@@ -47,6 +48,10 @@ ASH_EXPORT bool IsWindowMinimized(aura::Window* window);
 // Moves the window to the center of the display.
 ASH_EXPORT void CenterWindow(aura::Window* window);
 
+// Adjusts |bounds| so that the size does not exceed |max_size|.
+ASH_EXPORT void AdjustBoundsSmallerThan(const gfx::Size& max_size,
+                                        gfx::Rect* bounds);
+
 // Move the given bounds inside the given |visible_area| in parent coordinates,
 // including a safety margin given by |kMinimumOnScreenArea|.
 // This also ensures that the top of the bounds is visible.