Corrects viewport dimensions in chrome 54

Before these changes, the viewport height returned by chrome was equal
to the document height (at least in quirks mode)

Author: ChristophKaser

src/main/resources/js/viewport-height.js

@@ -1 +1 @@
-return Math.max(document.documentElement.clientHeight, window.innerHeight || 0);
+return window.innerHeight || document.documentElement.clientHeight || document.body.clientHeight;

src/main/resources/js/viewport-width.js

@@ -1 +1 @@
-return Math.max(document.documentElement.clientWidth, window.innerWidth || 0);
+return window.innerWidth || document.documentElement.clientWidth || document.body.clientWidth;