Implement Desktop Media Picker (Mac version) for Desktop Capture API

chrome/browser/ui/cocoa/media_picker/desktop_media_picker_item.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/media_picker/desktop_media_picker_item.h"
+
+#include "chrome/browser/media/desktop_media_picker_model.h"
+
+@implementation DesktopMediaPickerItem
+
+- (id)initWithSourceId:(content::DesktopMediaID)sourceID
+              imageUID:(int)imageUID
+            imageTitle:(NSString*)imageTitle {
+  if ((self = [super init])) {
+    sourceID_ = sourceID;
+    imageUID_.reset([[NSString stringWithFormat:@"%d", imageUID] retain]);
+    imageTitle_.reset([imageTitle retain]);
+  }
+  return self;
+}
+
+- (content::DesktopMediaID)sourceID {
+  return sourceID_;
+}
+
+- (void)setImageRepresentation:(NSImage*)image {
+  image_.reset([image retain]);
+  imageVersion_++;
+}
+
+- (void)setImageTitle:(NSString*)imageTitle {
+  imageTitle_.reset([imageTitle copy]);
+}
+
+#pragma mark IKImageBrowserItem
+
+- (NSString*)imageUID {
+  return imageUID_;
+}
+
+- (NSString*)imageRepresentationType {
+  // N.B. using the string instead of the constant because the latter is not in
+  // QuartzCore, and it would be the only thing in the project requiring the
+  // Quartz framework.
+  return @"IKImageBrowserNSImageRepresentationType";
+}
+
+- (NSString*)imageTitle {
+  return imageTitle_.get();
+}
+
+- (NSUInteger)imageVersion {
+  return imageVersion_;
+}
+
+- (id)imageRepresentation {
+  return image_.get();
+}
+
+@end  // @interface DesktopMediaPickerItem