Upstream Chrome on iOS source code [4/11].

ios/chrome/browser/ui/collection_view/cells/test_utils.mm

+// Copyright 2016 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 "ios/chrome/browser/ui/collection_view/cells/test_utils.h"
+
+namespace ios_internal {
+
+UIImage* CollectionViewTestImage() {
+  CGRect rect = CGRectMake(0.0, 0.0, 1.0, 1.0);
+  UIGraphicsBeginImageContext(rect.size);
+  CGContextRef context = UIGraphicsGetCurrentContext();
+
+  CGContextSetFillColorWithColor(context, [UIColor blueColor].CGColor);
+  CGContextFillRect(context, rect);
+
+  UIImage* image = UIGraphicsGetImageFromCurrentImageContext();
+  UIGraphicsEndImageContext();
+
+  return image;
+}
+
+}  // namespace ios_internal