Merge commit '7621e2f8dec938cf48181c8b10afc9b01f444e68' into beta

submodules/lottie-ios/Sources/Private/MainThread/LayerContainers/Utility/CachedImageProvider.swift

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+// Created by Jianjun Wu on 2022/5/12.
+// Copyright © 2022 Airbnb Inc. All rights reserved.
+
+import CoreGraphics
+import Foundation
+
+// MARK: - CachedImageProvider
+
+private final class CachedImageProvider: AnimationImageProvider {
+
+  // MARK: Lifecycle
+
+  /// Initializes an image provider with an image provider
+  ///
+  /// - Parameter imageProvider: The provider to load image from asset
+  ///
+  public init(imageProvider: AnimationImageProvider) {
+    self.imageProvider = imageProvider
+  }
+
+  // MARK: Public
+
+  public func imageForAsset(asset: ImageAsset) -> CGImage? {
+    if let image = imageCache.object(forKey: asset.id as NSString) {
+      return image
+    }
+    if let image = imageProvider.imageForAsset(asset: asset) {
+      imageCache.setObject(image, forKey: asset.id as NSString)
+      return image
+    }
+    return nil
+  }
+
+  // MARK: Internal
+
+  let imageCache: NSCache<NSString, CGImage> = .init()
+  let imageProvider: AnimationImageProvider
+}
+
+extension AnimationImageProvider {
+  /// Create a cache enabled image provider which will reuse the asset image with the same asset id
+  /// It wraps the current provider as image loader, and uses `NSCache` to cache the images for resue.
+  /// The cache will be reset when the `animation` is reset.
+  var cachedImageProvider: AnimationImageProvider {
+    CachedImageProvider(imageProvider: self)
+  }
+}