GUACAMOLE-352: Remove margin and padding from input sink.

guacamole-common-js/src/main/webapp/modules/Keyboard.js

@@ -1443,6 +1443,8 @@ Guacamole.Keyboard.InputSink = function InputSink() {
     field.style.position   = 'fixed';
     field.style.outline    = 'none';
     field.style.border     = 'none';
+    field.style.margin     = '0';
+    field.style.padding    = '0';
     field.style.height     = '0';
     field.style.width      = '0';
     field.style.left       = '0';