Refactor touch hit-testing hover/active tests.

LayoutTests/fast/events/touch/resources/touch-hover-active-tests.js

+function isBoxOfColor(givenColor)
+{
+    return function(e, quiet)
+    {
+        var color = window.getComputedStyle(e).backgroundColor;
+        if (color == givenColor)
+            return true;
+        if (!quiet)
+            testFailed('Box had backgroundColor: ' + color);

[Rick Byers, 2014/03/14 17:01:02]

seems like it would be a lot more understandable if the test reported the
observed state instead of the color (which is just an implementation detail) in
case of a failure.  Maybe have a list mapping colors to state names (eg.
'active')?

+        return false;
+    }
+}
+
+function elementCenter(e)
+{
+    return {
+        x: e.offsetLeft + e.offsetWidth / 2,
+        y: e.offsetTop + e.offsetHeight / 2
+    }
+}
+
+// Generate methods
+window.isBoxDefault = isBoxOfColor("rgb(0, 0, 255)");
+window.isBoxHovered = isBoxOfColor("rgb(255, 0, 0)");

[Rick Byers, 2014/03/14 17:01:02]

the name of this function and that below is a little misleading (i.e.
isBoxHovered returns false for something that's hovered and also active).  You
should at least have a comment making that clear, or update the name.

Combined with the above you could just have a single getHoverActiveState
function that returns a string that callers check.

+window.isBoxActive = isBoxOfColor("rgb(0, 255, 0)");
+window.isBoxHoveredAndActive = isBoxOfColor("rgb(255, 255, 0)");