Auto merge of #20253 - servo-wpt-sync:wpt_update_08-03-2018, r=jdm

Sync WPT with upstream (08-03-2018)

Automated downstream sync of changes from upstream as of 08-03-2018.
[no-wpt-sync]

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1 files changed, 16 insertions, 0 deletions

diff --git a/tests/wpt/web-platform-tests/common/arrays.js b/tests/wpt/web-platform-tests/common/arrays.js
new file mode 100644
index 00000000000..49431dd78ad
--- /dev/null
+++ b/tests/wpt/web-platform-tests/common/arrays.js
@@ -0,0 +1,16 @@
+// Returns true if the given arrays are equal. Optionally can pass an equality function.
+export function areArraysEqual(a, b, equalityFunction = (c, d) => { return c === d; }) {
+  try {
+    if (a.length !== b.length)
+      return false;
+
+    for (let i = 0; i < a.length; i++) {
+      if (!equalityFunction(a[i], b[i]))
+        return false;
+    }
+  } catch (ex) {
+    return false;
+  }
+
+  return true;
+}