Don't require expectations file for DumpAccessibility tests.

content/browser/accessibility/accessibility_tree_formatter_mac.mm

Index: content/browser/accessibility/accessibility_tree_formatter_mac.mm
diff --git a/content/browser/accessibility/accessibility_tree_formatter_mac.mm b/content/browser/accessibility/accessibility_tree_formatter_mac.mm
index fd5747fad82c3b6de147f8a2f5ea209a5169983f..c3798005655d272f724ad4ee01a7b3261f262377 100644
--- a/content/browser/accessibility/accessibility_tree_formatter_mac.mm
+++ b/content/browser/accessibility/accessibility_tree_formatter_mac.mm
@@ -300,12 +300,6 @@ base::string16 AccessibilityTreeFormatter::ToString(
 
 // static
 const base::FilePath::StringType
-AccessibilityTreeFormatter::GetActualFileSuffix() {
-  return FILE_PATH_LITERAL("-actual-mac.txt");
-}
-
-// static
-const base::FilePath::StringType
 AccessibilityTreeFormatter::GetExpectedFileSuffix() {
   return FILE_PATH_LITERAL("-expected-mac.txt");
 }