"NEW followed by no DUP was found" check is probably not necessary

[shifujun]

javassist/src/main/javassist/convert/TransformNewClass.java

Lines 59 to 61 in 700be6f

	if (iterator.byteAt(pos + 3) != DUP)
	throw new CannotCompileException(
	"NEW followed by no DUP was found");

When I use replaceNew with this lib: implementation 'com.google.android.gms:play-services-ads:22.0.0'.
It contains a class(com.google.android.gms.internal.ads.zzceh) maybe ProGuard processed, like this:

0: aload         4
         2: getfield      #236                // Field android/os/Message.obj:Ljava/lang/Object;
         5: checkcast     #30                 // class android/webkit/WebView$WebViewTransport
         8: astore_2
         9: new           #32                 // class android/webkit/WebView
        12: astore_3
        13: aload_3
        14: aload_1
        15: invokevirtual #237                // Method android/webkit/WebView.getContext:()Landroid/content/Context;
        18: invokespecial #240                // Method android/webkit/WebView."<init>":(Landroid/content/Context;)V
        21: aload_0

Then I learned why DUP followed NEW in https://stackoverflow.com/a/8594701/11616914 .

Now I think maybe javac always generate "new+dup", but the "dup" maybe not always useful.
So I guess tool like ProGuard maybe remove useless dup instructions.