Mark RenderFrameHostManagerTest.AllowTargetedNavigationsAfterSwap as flaky under TSANv2.

content/browser/frame_host/render_frame_host_manager_browsertest.cc

Index: content/browser/frame_host/render_frame_host_manager_browsertest.cc
===================================================================
--- content/browser/frame_host/render_frame_host_manager_browsertest.cc	(revision 287590)
+++ content/browser/frame_host/render_frame_host_manager_browsertest.cc	(working copy)
@@ -337,8 +337,17 @@
 
 // Test for crbug.com/116192.  Targeted links should still work after the
 // named target window has swapped processes.
+//
+// Flaky under TSANv2. http://crbug.com/400850
+#if defined(THREAD_SANITIZER)
+#define MAYBE_AllowTargetedNavigationsAfterSwap \
+    DISABLED_AllowTargetedNavigationsAfterSwap
+#else
+#define MAYBE_AllowTargetedNavigationsAfterSwap \
+    AllowTargetedNavigationsAfterSwap
+#endif
 IN_PROC_BROWSER_TEST_F(RenderFrameHostManagerTest,
-                       AllowTargetedNavigationsAfterSwap) {
+                       MAYBE_AllowTargetedNavigationsAfterSwap) {
   StartServer();
 
   // Load a page with links that open in a new window.