[Sheriff] Disable TaskManagerExistingPrintPreview for being flaky on Mac.

chrome/browser/ui/webui/print_preview/print_preview_ui_browsertest.cc

Index: chrome/browser/ui/webui/print_preview/print_preview_ui_browsertest.cc
diff --git a/chrome/browser/ui/webui/print_preview/print_preview_ui_browsertest.cc b/chrome/browser/ui/webui/print_preview/print_preview_ui_browsertest.cc
index 2afff16deedaa15fda42dd458fd848b3c9ae03cc..993854d5c7947161fd8634d36245fd26d224433e 100644
--- a/chrome/browser/ui/webui/print_preview/print_preview_ui_browsertest.cc
+++ b/chrome/browser/ui/webui/print_preview/print_preview_ui_browsertest.cc
@@ -103,7 +103,14 @@ IN_PROC_BROWSER_TEST_F(PrintPreviewTest, TaskManagerNewPrintPreview) {
   ASSERT_NO_FATAL_FAILURE(WaitForTaskManagerRows(1, MatchPrint("about:blank")));
 }
 
-IN_PROC_BROWSER_TEST_F(PrintPreviewTest, TaskManagerExistingPrintPreview) {
+// Disable the test for mac as it started being flaky, see http://crbug/367665.
+#if defined(OS_MACOSX) && !defined(OS_IOS)
+#define MAYBE_TaskManagerExistingPrintPreview DISABLED_TaskManagerExistingPrintPreview
+#else
+#define MAYBE_TaskManagerExistingPrintPreview TaskManagerExistingPrintPreview
+#endif
+IN_PROC_BROWSER_TEST_F(PrintPreviewTest,
+                       MAYBE_TaskManagerExistingPrintPreview) {
   // Create the print preview dialog.
   Print();