Remove CreateGuestBrowser function from ChromeOS.

InProcessBrowserTest::CreateGuestBrowser does not work on ChromeOS and
to create a Guest browser, proper switches need to be added while
setting up the test.
The function is excluded from ChromeOS build.

Bug: 1125474
Change-Id: If14266e1a1372ebec4e4ae92c0fea16164d726f8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2490007
Commit-Queue: Ramin Halavati <rhalavati@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Reviewed-by: Marc Treib <treib@chromium.org>
Cr-Commit-Position: refs/heads/master@{#820180}

chrome/browser/metrics/ukm_browsertest.cc

@@ -474,7 +474,7 @@ IN_PROC_BROWSER_TEST_F(UkmBrowserTest, IncognitoPlusRegularCheck) {
 }
 
 // Make sure that UKM is disabled while a guest profile's window is open.
-#if !defined(OS_ANDROID)
+#if !defined(OS_ANDROID) && !defined(CHROME_OS)
 IN_PROC_BROWSER_TEST_F(UkmBrowserTest, RegularPlusGuestCheck) {
   ukm::UkmTestHelper ukm_test_helper(GetUkmService());
   MetricsConsentOverride metrics_consent(true);
@@ -500,7 +500,7 @@ IN_PROC_BROWSER_TEST_F(UkmBrowserTest, RegularPlusGuestCheck) {
   harness->service()->GetUserSettings()->SetSyncRequested(false);
   CloseBrowserSynchronously(regular_browser);
 }
-#endif  // !defined(OS_ANDROID)
+#endif  // !defined(OS_ANDROID) && !defined(CHROME_OS)
 
 // Make sure that UKM is disabled while an non-sync profile's window is open.
 #if !defined(OS_ANDROID)

chrome/test/base/in_process_browser_test.cc

@@ -497,7 +497,7 @@ Browser* InProcessBrowserTest::CreateBrowserForApp(const std::string& app_name,
 }
 #endif  // !defined(OS_MAC)
 
-#if !defined(OS_ANDROID)
+#if !defined(OS_ANDROID) && !defined(CHROME_OS)
 Browser* InProcessBrowserTest::CreateGuestBrowser() {
   // Get Guest profile.
   ProfileManager* profile_manager = g_browser_process->profile_manager();
@@ -518,7 +518,7 @@ Browser* InProcessBrowserTest::CreateGuestBrowser() {
   AddBlankTabAndShow(browser);
   return browser;
 }
-#endif
+#endif  // !defined(OS_ANDROID) && !defined(CHROME_OS)
 
 void InProcessBrowserTest::AddBlankTabAndShow(Browser* browser) {
   content::WindowedNotificationObserver observer(

chrome/test/base/in_process_browser_test.h

@@ -227,8 +227,11 @@ class InProcessBrowserTest : public content::BrowserTestBase {
   // is omitted, the currently active profile will be used.
   Browser* CreateIncognitoBrowser(Profile* profile = nullptr);
 
-#if !defined(OS_ANDROID)
+#if !defined(OS_ANDROID) && !defined(CHROME_OS)
   // Similar to |CreateBrowser|, but creates a Guest browser.
+  // To create a Guest browser for ChromeOS, you need to add proper switches to
+  // commandline while setting up the test. For an example see
+  // AppListClientGuestModeBrowserTest::SetUpCommandLine.
   Browser* CreateGuestBrowser();
 #endif