[sheriff] Disable MediaHistoryWebUIBrowserTest.All on Windows.

R=beccahughes@chromium.org
TBR=beccahughes@chromium.org

Bug: 1045500
Change-Id: I19500599b2c459081584dcab9145452e8a9b06d3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2019384Reviewed-by: François Doray <fdoray@chromium.org>
Commit-Queue: François Doray <fdoray@chromium.org>
Cr-Commit-Position: refs/heads/master@{#735058}

chrome/test/data/webui/media/media_history_webui_browsertest.js

@@ -6,6 +6,7 @@
  * @fileoverview Test suite for the Media History WebUI.
  */
 
+GEN('#include "build/build_config.h"');
 GEN('#include "chrome/browser/ui/browser.h"');
 GEN('#include "media/base/media_switches.h"');
 
@@ -26,7 +27,14 @@ MediaHistoryWebUIBrowserTest.prototype = {
   ],
 };
 
-TEST_F('MediaHistoryWebUIBrowserTest', 'All', function() {
+// https://crbug.com/1045500: Flaky on Windows.
+GEN('#if defined(OS_WIN)');
+GEN('#define MAYBE_All DISABLED_All');
+GEN('#else');
+GEN('#define MAYBE_All All');
+GEN('#endif');
+
+TEST_F('MediaHistoryWebUIBrowserTest', 'MAYBE_All', function() {
   suiteSetup(function() {
     return whenPageIsPopulatedForTest();
   });