Upstream Chrome on iOS source code [8/11].

ios/chrome/browser/ui/settings/utils/resized_avatar_cache.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/settings/utils/resized_avatar_cache.h"
+
+#include "base/mac/scoped_nsobject.h"
+#import "ios/chrome/browser/ui/uikit_ui_util.h"
+#include "ios/public/provider/chrome/browser/chrome_browser_provider.h"
+#import "ios/public/provider/chrome/browser/signin/chrome_identity.h"
+#import "ios/public/provider/chrome/browser/signin/chrome_identity_service.h"
+#include "ios/public/provider/chrome/browser/signin/signin_resources_provider.h"
+
+namespace {
+const CGFloat kAccountProfilePhotoDimension = 40.0f;
+}  // namespace
+
+@implementation ResizedAvatarCache {
+  // Retains resized images. Key is Chrome Identity.
+  base::scoped_nsobject<NSCache<ChromeIdentity*, UIImage*>> _resizedImages;
+
+  // Holds weak references to the cached avatar image from the
+  // ChromeIdentityService. Key is Chrome Identity.
+  base::scoped_nsobject<NSMapTable<ChromeIdentity*, UIImage*>> _originalImages;
+}
+
+- (instancetype)init {
+  self = [super init];
+  if (self) {
+    _resizedImages.reset([[NSCache alloc] init]);
+    _originalImages.reset([[NSMapTable strongToWeakObjectsMapTable] retain]);
+  }
+  return self;
+}
+
+- (UIImage*)resizedAvatarForIdentity:(ChromeIdentity*)identity {
+  UIImage* image = ios::GetChromeBrowserProvider()
+                       ->GetChromeIdentityService()
+                       ->GetCachedAvatarForIdentity(identity);
+  if (!image) {
+    image = ios::GetChromeBrowserProvider()
+                ->GetSigninResourcesProvider()
+                ->GetDefaultAvatar();
+    // No cached image, trigger a fetch, which will notify all observers.
+    ios::GetChromeBrowserProvider()
+        ->GetChromeIdentityService()
+        ->GetAvatarForIdentity(identity, ^(UIImage*){
+                               });
+  }
+
+  // If the currently used image has already been resized, use it.
+  if ([_resizedImages objectForKey:identity] &&
+      [_originalImages objectForKey:identity] == image)
+    return [_resizedImages objectForKey:identity];
+
+  [_originalImages setObject:image forKey:identity];
+
+  // Resize the profile image.
+  CGFloat dimension = kAccountProfilePhotoDimension;
+  if (image.size.width != dimension || image.size.height != dimension) {
+    image = ResizeImage(image, CGSizeMake(dimension, dimension),
+                        ProjectionMode::kAspectFit);
+  }
+  [_resizedImages setObject:image forKey:identity];
+  return image;
+}
+
+@end