Create c/b/ui/cocoa/test and move test files to there

chrome/browser/ui/cocoa/omnibox/omnibox_popup_matrix_unittest.mm

 // Copyright (c) 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.
 
 #import "chrome/browser/ui/cocoa/omnibox/omnibox_popup_cell.h"
 #import "chrome/browser/ui/cocoa/omnibox/omnibox_popup_matrix.h"
 
 #include <stddef.h>
 
 #include "base/macros.h"
-#import "chrome/browser/ui/cocoa/cocoa_test_helper.h"
+#import "chrome/browser/ui/cocoa/test/cocoa_test_helper.h"
 #import "ui/events/test/cocoa_test_event_utils.h"
 
 namespace {
 
 NSEvent* MouseEventInRow(OmniboxPopupMatrix* matrix,
                          NSEventType type,
                          NSInteger row) {
   NSRect cell_rect = [matrix rectOfRow:row];
   NSPoint point_in_view = NSMakePoint(NSMidX(cell_rect), NSMidY(cell_rect));
   NSPoint point_in_window = [matrix convertPoint:point_in_view toView:nil];
@@ skipping 64 matching lines @@
 TEST_F(OmniboxPopupMatrixTest, SelectedRow) {
   [NSApp postEvent:MouseEventInRow(matrix_, NSLeftMouseUp, 2) atStart:YES];
   [matrix_ mouseDown:MouseEventInRow(matrix_, NSLeftMouseDown, 2)];
 
   EXPECT_EQ(2u, selected_row_);
   EXPECT_EQ(2u, clicked_row_);
   EXPECT_EQ(0u, middle_clicked_row_);
 }
 
 }  // namespace