Fix warnings and improve time

Sources/Cache/Storage.swift

@@ -58,7 +58,7 @@ public enum StorageExpiration {
         case .seconds(let seconds):
             return date.addingTimeInterval(seconds)
         case .days(let days):
-            let duration = TimeInterval(TimeConstants.secondsInOneDay) * TimeInterval(days)
+            let duration: TimeInterval = TimeInterval(TimeConstants.secondsInOneDay) * TimeInterval(days)
             return date.addingTimeInterval(duration)
         case .date(let ref):
             return ref

Sources/General/KF.swift

@@ -250,7 +250,6 @@ extension KF.Builder {
     ///            This value is `nil` if the image is being loaded from cache.
     @discardableResult
     public func set(to interfaceImage: WKInterfaceImage) -> DownloadTask? {
-        let placeholderImage = placeholder as? KFCrossPlatformImage ?? nil
         return interfaceImage.kf.setImage(
             with: source,
             placeholder: placeholder,

Sources/General/KingfisherOptionsInfo.swift

@@ -379,15 +379,15 @@ class ImageLoadingProgressSideEffect: DataReceivingSideEffect {
     }
 
     func onDataReceived(_ session: URLSession, task: SessionDataTask, data: Data) {
-        DispatchQueue.main.async {
-            guard self.onShouldApply() else { return }
-            guard let expectedContentLength = task.task.response?.expectedContentLength,
-                      expectedContentLength != -1 else
-            {
-                return
-            }
+        guard self.onShouldApply() else { return }
+        guard let expectedContentLength = task.task.response?.expectedContentLength,
+                  expectedContentLength != -1 else
+        {
+            return
+        }
 
-            let dataLength = Int64(task.mutableData.count)
+        let dataLength = Int64(task.mutableData.count)
+        DispatchQueue.main.async {
             self.block(dataLength, expectedContentLength)
         }
     }