Expose thumbnails of pages to iOS share extensions.

ui/base/test/ios/ui_image_test_utils.h

+// Copyright 2017 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.
+
+#ifndef UI_BASE_TEST_IOS_UI_IMAGE_TEST_UTILS_H_
+#define UI_BASE_TEST_IOS_UI_IMAGE_TEST_UTILS_H_
+
+#import <UIKit/UIKit.h>
+
+namespace ui {
+namespace test {
+namespace uiimage_utils {
+
+// Returns a new UIImage of size |size| with a solid color of |color|.
+UIImage* UIImageWithSizeAndSolidColor(CGSize const& size, UIColor* color);
+
+// Disclaimer, testing function with plenty of limitations:
+// Requires the UIImages to be backed by a CGImage, ignores colorspace, may
+// return false negatives, not efficient, and probably other things.
+//
+// Returns whether the pixels in |image1| are equal to the pixels in |image2|.

[sdefresne, 2017/01/30 16:56:20]

Either use image1 in method too or use image_1 in comment :-)

[jif, 2017/02/03 10:54:49]

Done.

+// This is unlike UIImage's |isEqual:| method which only returns YES if the
+// memory backing the images is the same.
+bool UIImagesAreEqual(UIImage* image_1, UIImage* image_2);
+
+}  // namespace uiimage_utils
+}  // namespace test
+}  // namespace ui
+
+#endif  // UI_BASE_TEST_IOS_UI_IMAGE_TEST_UTILS_H_