Removes a tracing CHECK supposed to investigate infinite SetAutoHideBehavior

ash/shelf/shelf_layout_manager_unittest.cc

Index: ash/shelf/shelf_layout_manager_unittest.cc
diff --git a/ash/shelf/shelf_layout_manager_unittest.cc b/ash/shelf/shelf_layout_manager_unittest.cc
index 550307ec8f18694db8aab6b24e3cc5d424ccef56..b5ee95f46135005be47e053609ad303f6cbdabde 100644
--- a/ash/shelf/shelf_layout_manager_unittest.cc
+++ b/ash/shelf/shelf_layout_manager_unittest.cc
@@ -581,10 +581,6 @@ void ShelfLayoutManagerTest::RunGestureDragTests(gfx::Vector2d delta) {
   EXPECT_EQ(SHELF_AUTO_HIDE, shelf->GetVisibilityState());
   EXPECT_EQ(SHELF_AUTO_HIDE_SHOWN, shelf->GetAutoHideState());
   EXPECT_EQ(SHELF_AUTO_HIDE_BEHAVIOR_ALWAYS, shelf->auto_hide_behavior());
-
-  // Avoid a CHECK that makes sure SetAutoHideBehavior is not called too
-  // frequently. This is to help investigate http://crbug.com/665093 .
-  shelf->count_auto_hide_changes_ = 0;
 }
 
 // Makes sure SetVisible updates work area and widget appropriately.