Show diffs involving root-level asymmetric equality testers

* Fixes #1831

src/core/matchers/DiffBuilder.js

@@ -72,12 +72,7 @@ getJasmineRequireObj().DiffBuilder = function (j$) {
   };
 
   function dereferencePath(objectPath, actual, expected, pp) {
-    var i, asymmetricResult;
-
-    for (i = 0; i < objectPath.components.length; i++) {
-      actual = actual[objectPath.components[i]];
-      expected = expected[objectPath.components[i]];
-
+    function handleAsymmetricExpected() {
       if (j$.isAsymmetricEqualityTester_(expected) && j$.isFunction_(expected.valuesForDiff_)) {
         var asymmetricResult = expected.valuesForDiff_(actual, pp);
         expected = asymmetricResult.self;
@@ -85,6 +80,15 @@ getJasmineRequireObj().DiffBuilder = function (j$) {
       }
     }
 
+    var i;
+    handleAsymmetricExpected();
+
+    for (i = 0; i < objectPath.components.length; i++) {
+      actual = actual[objectPath.components[i]];
+      expected = expected[objectPath.components[i]];
+      handleAsymmetricExpected();
+    }
+
     return {actual: actual, expected: expected};
   }