oopif: disable spellcheck panel test on Mac

It's quite flaky and I can't immediately figure out how to fix it.

Bug: 1032617,1018849
Change-Id: Ibee6b16aba3947601dd47b3fa290734bf076db23
Tbr: nasko@chromium.org
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1959932Reviewed-by: Elly Fong-Jones <ellyjones@chromium.org>
Commit-Queue: Elly Fong-Jones <ellyjones@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723476}

chrome/browser/site_isolation/spellcheck_per_process_browsertest.cc

@@ -297,7 +297,14 @@ IN_PROC_BROWSER_TEST_F(ChromeSitePerProcessTest, OOPIFDisabledSpellCheckTest) {
 #if BUILDFLAG(HAS_SPELLCHECK_PANEL)
 // Tests that the OSX spell check panel can be opened from an out-of-process
 // subframe, crbug.com/712395
-IN_PROC_BROWSER_TEST_F(ChromeSitePerProcessTest, OOPIFSpellCheckPanelTest) {
+#if defined(OS_MACOSX)
+// https://crbug.com/1032617
+#define MAYBE_OOPIFSpellCheckPanelTest DISABLED_OOPIFSpellCheckPanelTest
+#else
+#define MAYBE_OOPIFSpellCheckPanelTest OOPIFSpellCheckPanelTest
+#endif
+IN_PROC_BROWSER_TEST_F(ChromeSitePerProcessTest,
+                       MAYBE_OOPIFSpellCheckPanelTest) {
   spellcheck::SpellCheckPanelBrowserTestHelper test_helper;
 
   GURL main_url(embedded_test_server()->GetURL(