selection: Update addRange-nn.html for 20170227 draft.

third_party/WebKit/LayoutTests/external/wpt/selection/addRange.js

 "use strict";
 
 function testAddRange(exception, range, endpoints, qualifier, testName) {
     if (!isSelectableNode(endpoints[0]) || !isSelectableNode(endpoints[2])) {
-        test(function() {
-            assert_equals(exception, null, "Test setup must not throw exceptions");
-
-            assertSelectionNoChange(function() { selection.addRange(range); });
-            assert_equals(range.startContainer, endpoints[0],
-                "addRange() must not modify the startContainer of the Range it's given");
-            assert_equals(range.startOffset, endpoints[1],
-                "addRange() must not modify the startOffset of the Range it's given");
-            assert_equals(range.endContainer, endpoints[2],
-                "addRange() must not modify the endContainer of the Range it's given");
-            assert_equals(range.endOffset, endpoints[3],
-                "addRange() must not modify the endOffset of the Range it's given");
-        }, testName + ": " + qualifier + " addRange() must do nothing");
+        testAddRangeDoesNothing(exception, range, endpoints, qualifier, testName);
         return;
     }
 
     test(function() {
         assert_equals(exception, null, "Test setup must not throw exceptions");
 
         selection.addRange(range);
 
         assert_equals(range.startContainer, endpoints[0],
             "addRange() must not modify the startContainer of the Range it's given");
@@ skipping 92 matching lines @@
             "After " + qualifier + " addRange(), after mutating the Selection's last Range, startContainer of the Selection's last Range must match the added Range");
         assert_equals(newRange.startOffset, range.startOffset,
             "After " + qualifier + " addRange(), after mutating the Selection's last Range, startOffset of the Selection's last Range must match the added Range");
         assert_equals(newRange.endContainer, range.endContainer,
             "After " + qualifier + " addRange(), after mutating the Selection's last Range, endContainer of the Selection's last Range must match the added Range");
         assert_equals(newRange.endOffset, range.endOffset,
             "After " + qualifier + " addRange(), after mutating the Selection's last Range, endOffset of the Selection's last Range must match the added Range");
     }, testName + ": modifying the Selection's last Range must modify the " + qualifier + " added Range");
 }
 
+function testAddRangeDoesNothing(exception, range, endpoints, qualifier, testName) {
+    test(function() {
+        assert_equals(exception, null, "Test setup must not throw exceptions");
+
+        assertSelectionNoChange(function() { selection.addRange(range); });
+        assert_equals(range.startContainer, endpoints[0],
+            "addRange() must not modify the startContainer of the Range it's given");
+        assert_equals(range.startOffset, endpoints[1],
+            "addRange() must not modify the startOffset of the Range it's given");
+        assert_equals(range.endContainer, endpoints[2],
+            "addRange() must not modify the endContainer of the Range it's given");
+        assert_equals(range.endOffset, endpoints[3],
+            "addRange() must not modify the endOffset of the Range it's given");
+    }, testName + ": " + qualifier + " addRange() must do nothing");
+}
+
 // Do only n evals, not n^2
 var testRangesEvaled = testRanges.map(eval);
 
 // Run a subset of all of addRange tests.
 // Huge number of tests in a single file causes problems. Each of
 // addRange-NN.html runs a part of them.
 //
 // startIndex - Start index in testRanges array
 // optionalEndIndex - End index in testRanges array + 1. If this argument is
 //     omitted, testRanges.length is applied.
@@ skipping 47 matching lines @@
                 }
                 if (range2.endOffset !== endpoints2[3]) {
                     throw "Sanity check: the second Range we created must have the desired endOffset";
                 }
             } catch (e) {
                 exception = e;
             }
 
             testAddRange(exception, range1, endpoints1, "first", testName);
             if (selection.rangeCount > 0)
-                testAddRange(exception, range2, endpoints2, "second", testName);
+                testAddRangeDoesNothing(exception, range2, endpoints2, "second", testName);
         }
     }
 }