Revert "ShapeUtis.size should return 0 if the tensor dims is empty in…

…stead of 1."

This reverts commit d8aeee1.

js/web/lib/wasm/jsep/util.ts

@@ -102,7 +102,7 @@ export class ShapeUtil {
    * calculate the size (number of elements)
    */
   static size(dims: readonly number[]): number {
-    return dims.length > 0 ? ShapeUtil.getSizeFromDimensionRange(dims, 0, dims.length) : 0;
+    return ShapeUtil.getSizeFromDimensionRange(dims, 0, dims.length);
   }
 
   /**