DevTools: fix text offset when selection ends on expand triangle

third_party/WebKit/LayoutTests/inspector/console/console-copy-truncated-text.html

Index: third_party/WebKit/LayoutTests/inspector/console/console-copy-truncated-text.html
diff --git a/third_party/WebKit/LayoutTests/inspector/console/console-copy-truncated-text.html b/third_party/WebKit/LayoutTests/inspector/console/console-copy-truncated-text.html
index 6cd952915862ac061ae2c0ee964995b3c587da23..55f0fe6d02e7eb294c2fa1515d107b1b3cc4ca05 100644
--- a/third_party/WebKit/LayoutTests/inspector/console/console-copy-truncated-text.html
+++ b/third_party/WebKit/LayoutTests/inspector/console/console-copy-truncated-text.html
@@ -12,6 +12,7 @@ function test()
     var shortUrlWithHashes = "www." + "0123456789".repeat(2) + "zfoobarz" + "0123456789".repeat(2);
     var urlWithHashes = "www." + "0123456789".repeat(2) + "z".repeat(150) + "0123456789".repeat(2);
     var highlightedUrl = "www." + "z".repeat(200) + ".com";
+    var longUrlInMessageWithNonTextNodePrefix = "www." + "z123456789".repeat(15) + ".com";
     var prepareCode = `
         // Keep this as the first url logged to record the max truncated length.
         console.log("${longUrl}");
@@ -22,9 +23,10 @@ function test()
         console.log("${shortUrlWithHashes}");
         console.log("${urlWithHashes}");
         console.log("${highlightedUrl}");
+        console.log("${longUrlInMessageWithNonTextNodePrefix}");
     `;
 
-    var expectedMessageCount = 8;
+    var expectedMessageCount = 9;
     var consoleView = Console.ConsoleView.instance();
     var viewport = Console.ConsoleView.instance()._viewport;
     var maxLength;
@@ -120,6 +122,25 @@ function test()
 
         function testSelectWithinHighlightedUrlEnd(next) {
             testHighlightedUrlWithSearchQuery(".com", next);
+        },
+
+        function testSelectionStartingInNonTextNode(next) {
+            var messageElement = consoleView.itemElement(8).element();
+
+            // Artificially insert an empty non-text node element in the beginning.
+            var artificialEmptyPrefixElement = createElementWithClass('div', 'artificialEmptyPrefixElement');
+            messageElement.insertBefore(artificialEmptyPrefixElement, messageElement.firstChild);
+
+            // Use .childNodes to ensure we get all nodes.
+            InspectorTest.addResult("\nMaking selection from empty prefix to end");
+            window.getSelection().setBaseAndExtent(artificialEmptyPrefixElement, 0, messageElement.lastChild, messageElement.childNodes.length - 1);
+
+            var selectedText = viewport._selectedText();
+            if (selectedText)
+                InspectorTest.addResult("Selection length: " + selectedText.length + ", " + "text: " + selectedText.replace(/\bVM:\d+/g, "VM"));
+            else
+                InspectorTest.addResult("No selection");
+            next();
         }
     ];