Disable a WebContentsImplBrowserTest due to timeout failure

TBR=sadrul@chromium.org

Bug: 978028
Change-Id: I6b7bad2afbe04b24a7326f54c411889495340e90
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1674148Reviewed-by: Huanzhong Huang <huanzhong@chromium.org>
Commit-Queue: Huanzhong Huang <huanzhong@chromium.org>
Cr-Commit-Position: refs/heads/master@{#671676}

content/browser/web_contents/web_contents_impl_browsertest.cc

@@ -2941,7 +2941,8 @@ IN_PROC_BROWSER_TEST_F(WebContentsImplBrowserTest, NotifyPreferencesChanged) {
   SetBrowserClientForTesting(old_client);
 }
 
-IN_PROC_BROWSER_TEST_F(WebContentsImplBrowserTest, SetPageFrozen) {
+// DISABLED: frquent timeout crbug.com/978028
+IN_PROC_BROWSER_TEST_F(WebContentsImplBrowserTest, DISABLED_SetPageFrozen) {
   EXPECT_TRUE(embedded_test_server()->Start());
 
   GURL test_url = embedded_test_server()->GetURL("/pause_schedule_task.html");