Disable flaky tests in ExtensionsMenuViewBrowserTest

Sample build failure where both failed:
https://ci.chromium.org/p/chromium/builders/ci/win-asan/10148

TBR=benwells@chromium.org

Change-Id: Iecc7d75fd41e2ded960ffdfd9e6f5f7bf3b3c8d0
Bug: 1048980,1049036
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2036069Reviewed-by: Mikel Astiz <mastiz@chromium.org>
Commit-Queue: Mikel Astiz <mastiz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#738530}

chrome/browser/ui/views/extensions/extensions_menu_view_browsertest.cc

@@ -382,8 +382,9 @@ IN_PROC_BROWSER_TEST_F(ExtensionsMenuViewBrowserTest,
   EXPECT_TRUE(GetVisibleToolbarActionViews().empty());
 }
 
+// TODO(crbug.com/1049036): Flaky on various platforms.
 IN_PROC_BROWSER_TEST_F(ExtensionsMenuViewBrowserTest,
-                       TriggeringExtensionClosesMenu) {
+                       DISABLED_TriggeringExtensionClosesMenu) {
   LoadTestExtension("extensions/trigger_actions/browser_action");
   ShowUi("");
   VerifyUi();
@@ -451,8 +452,9 @@ IN_PROC_BROWSER_TEST_F(ExtensionsMenuViewBrowserTest,
   DismissUi();
 }
 
+// TODO(crbug.com/1048980): Flaky on various platforms.
 IN_PROC_BROWSER_TEST_F(ExtensionsMenuViewBrowserTest,
-                       ManageExtensionsOpensExtensionsPage) {
+                       DISABLED_ManageExtensionsOpensExtensionsPage) {
   ShowUi("");
   VerifyUi();