Disable flaky test AccessibilityIpcErrorBrowserTest.ResetBrowserAccessibilityManager

TBR=kschmi@microsoft.com

Bug: 973946

Change-Id: I69b54fdfe9421acacaf98c2bcf684680e7cb66fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1659029
Commit-Queue: Oksana Zhuravlova <oksamyt@chromium.org>
Reviewed-by: Kurt Catti-Schmidt <kschmi@microsoft.com>
Cr-Commit-Position: refs/heads/master@{#669034}

content/browser/accessibility/accessibility_ipc_error_browsertest.cc

@@ -39,8 +39,9 @@ class AccessibilityIpcErrorBrowserTest : public ContentBrowserTest {
   DISALLOW_COPY_AND_ASSIGN(AccessibilityIpcErrorBrowserTest);
 };
 
+// Flaky on all platforms. http://crbug.com/973946
 IN_PROC_BROWSER_TEST_F(AccessibilityIpcErrorBrowserTest,
-                       ResetBrowserAccessibilityManager) {
+                       DISABLE_ResetBrowserAccessibilityManager) {
   // Create a data url and load it.
   const char url_str[] =
       "data:text/html,"