Squelch context menus on the OSX App List when both buttons are pressed.

ui/app_list/cocoa/apps_grid_controller_unittest.mm

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/mac/foundation_util.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/strings/utf_string_conversions.h"
 #include "skia/ext/skia_utils_mac.h"
 #import "testing/gtest_mac.h"
 #include "ui/app_list/app_list_constants.h"
@@ skipping 965 matching lines @@
 
   // Test a context menu request while the item is still installing.
   item_two_model->SetMenuReadyForTesting(false);
   menu = [page menuForEvent:mouse_at_cell_1];
   EXPECT_EQ(nil, menu);
 
   item_two_model->SetMenuReadyForTesting(true);
   menu = [page menuForEvent:mouse_at_cell_1];
   EXPECT_EQ(1, [menu numberOfItems]);
   EXPECT_NSEQ(@"Menu For: Item Two", [[menu itemAtIndex:0] title]);
+
+  // Test that a button being held down with the left button does not also show
+  // a context menu.
+  [GetItemViewAt(0) highlight:YES];
+  EXPECT_FALSE([page menuForEvent:mouse_at_cell_0]);
+  [GetItemViewAt(0) highlight:NO];
+  EXPECT_TRUE([page menuForEvent:mouse_at_cell_0]);
 }
 
 }  // namespace test
 }  // namespace app_list