update library/src/main/ets/ImageKnifeLoader.ets.

Signed-off-by: 田双明 <tianshuangming@h-partners.com>

library/src/main/ets/ImageKnifeLoader.ets

@@ -389,27 +389,27 @@ export class ImageKnifeLoader {
   }
 
     static downsamplerReqSize(typeValue: string, request: RequestJobRequest, size: Size,
-    SRC?: ImageKnifeRequestSource) {
+    SRC?: ImageKnifeRequestSource):image.DecodingOptions {
     let reqSize =
       new Downsampler().calculateScaling(typeValue, size.width, size.height, request.targetWidth, request.targetHeight,
         request.downsampType)
     if (typeValue == "svg") {
-      return ({
+      return {
         editable: true,
-        desiredSize: ({
+        desiredSize: {
           height: vp2px(reqSize.height),
           width: vp2px(reqSize.width)
-        } as Size)
+        }
 
-      } as image.DecodingOptions)
+      }
     } else {
-      return ({
+      return {
         editable: request.requestSource === SRC && request.transformation !== undefined ? true : false,
-        desiredSize: ({
+        desiredSize:{
           width: reqSize.width,
           height: reqSize.height
-        } as Size)
+        }
-      } as image.DecodingOptions)
+      }
     }
   }
 }