Add forEach() to CSSVariablesMap

LayoutTests/fast/css/variables/cssom-computed-style.html

Index: LayoutTests/fast/css/variables/cssom-computed-style.html
diff --git a/LayoutTests/fast/css/variables/cssom-computed-style.html b/LayoutTests/fast/css/variables/cssom-computed-style.html
index b293bd0aa433e4fb420bf87e39c839e7bd70b3d3..6889b6fc2b7719bac4dc21ee0a0068aebfaf175f 100644
--- a/LayoutTests/fast/css/variables/cssom-computed-style.html
+++ b/LayoutTests/fast/css/variables/cssom-computed-style.html
@@ -21,6 +21,9 @@ var preStyle = getComputedStyle(pre);
 var bodyStyle = getComputedStyle(document.querySelector("body"));
 pre.innerText += "Computed variables declaration: " + preStyle.var + "\n";
 
+pre.innerText += "Equal variables declaration objects on multiple accesses: ";
+pre.innerText += ((preStyle.var === preStyle.var) ? "pass": "fail") + "\n";
+
 pre.innerText += "Create variable: ";
 try {
     preStyle.var.set("create", "test");
@@ -37,6 +40,19 @@ pre.innerText += "Read inherited variable: " + preStyle.var.get("inherited") + "
 pre.innerText += "Read inline variable: " + preStyle.var.get("inline") + "\n";
 pre.innerText += "Read non-existent variable: " + (bodyStyle.var.get("test") ? "fail" : "pass") + "\n";
 
+pre.innerText += "Enumerate variables:\n";
+var varList = [];
+preStyle.var.forEach(function(value, name) { varList.push([name, value]); });
+varList.sort();

[arv (Not doing code reviews), 2013/08/07 14:16:23]

I'm still kind of concerned about this sort. The order of forEach should be
deterministic and the sort might hide a bug where the order isn't.

[alancutter (OOO until 2018), 2013/08/08 01:50:57]

The order of the computed style's forEach() is determined by the hash algorithm
used for AtomicString (which has been subject to change in recent times and
alter the ordering seen). The spec does not specify the order in which items are
accessed by forEach() so this test should be order agnostic.

The order in inline styles is much less dependent on unrelated things like hash
algorithms and where I test altering the variable map during the forEach() there
is a well defined expectation of ordering. For those tests it makes more sense
to remove the sort().

+for (var i = 0; i < varList.length; i++) {
+    pre.innerText += "    " + varList[i][0] + ": " + varList[i][1] + "\n";
+}
+
+pre.innerText += "Enumerate empty variables: ";
+var pass = true;
+bodyStyle.var.forEach(function(value, name) { pass = false; });
+pre.innerText += (pass ? "pass" : "fail") + "\n";
+
 pre.innerText += "Update variable: ";
 try {
     preStyle.var.set("inline", "test");