Add DataView.asHex()

Returns the DataView as an hex formatted string with a '/' indicating
the current offset position. Useful for debugging.

js/injected_methods.js

@@ -101,4 +101,15 @@ DataView.prototype.readString = function() {
         s += String.fromCharCode(c);
     }
     return s;
-};
+};
+
+DataView.prototype.asHex = function() {
+    let s = "";
+    for (let ii = 0; ii < this.byteLength; ii++) {
+        if (ii == this.offset) {
+            s += "/"
+        }
+        s += this.getUint8(ii).toString(16);
+    }
+    return s;
+};