Fix incognito_mode_prefs_unittest compile on Android.

chrome/browser/prefs/incognito_mode_prefs_unittest.cc

Index: chrome/browser/prefs/incognito_mode_prefs_unittest.cc
diff --git a/chrome/browser/prefs/incognito_mode_prefs_unittest.cc b/chrome/browser/prefs/incognito_mode_prefs_unittest.cc
index db1a3f4d117aaeca59a80b94cede8bc09dd7831b..b534fa5362d5edf91ad6770032f4c79d214ba216 100644
--- a/chrome/browser/prefs/incognito_mode_prefs_unittest.cc
+++ b/chrome/browser/prefs/incognito_mode_prefs_unittest.cc
@@ -62,6 +62,7 @@ typedef IncognitoModePrefsTest IncognitoModePrefsDeathTest;
 #define MAYBE_GetAvailabilityBadValue GetAvailabilityBadValue
 #endif
 
+#if GTEST_HAS_DEATH_TEST
 TEST_F(IncognitoModePrefsDeathTest, MAYBE_GetAvailabilityBadValue) {
   prefs_.SetUserPref(prefs::kIncognitoModeAvailability,
                      Value::CreateIntegerValue(-1));
@@ -79,3 +80,4 @@ TEST_F(IncognitoModePrefsDeathTest, MAYBE_GetAvailabilityBadValue) {
   }, "");
 #endif
 }
+#endif  // GTEST_HAS_DEATH_TEST