Upstream some more iOS switches.

ios/chrome/browser/chrome_switches.h

Index: ios/chrome/browser/chrome_switches.h
diff --git a/ios/chrome/browser/chrome_switches.h b/ios/chrome/browser/chrome_switches.h
index e6df544c6080f1611a03450080eb5b824b90b4c0..f1c590efdfae6f8a70172eac6ef2feeee5b441d1 100644
--- a/ios/chrome/browser/chrome_switches.h
+++ b/ios/chrome/browser/chrome_switches.h
@@ -9,11 +9,29 @@
 
 namespace switches {
 
+extern const char kDisableContextualSearch[];
+extern const char kDisableIOSFastWebScrollViewInsets[];
+extern const char kDisableIOSPasswordGeneration[];
+extern const char kDisableIOSPasswordSuggestions[];
 extern const char kDisableIOSWKWebView[];
+extern const char kDisableKeyboardCommands[];
+extern const char kDisableNTPFavicons[];
+extern const char kDisableOfflineAutoReload[];
+extern const char kDisableTabSwitcher[];
+
+extern const char kEnableContextualSearch[];
+extern const char kEnableCredentialManagerAPI[];
+extern const char kEnableIOSFastWebScrollViewInsets[];
+extern const char kEnableIOSHandoffToOtherDevices[];
+extern const char kEnableIOSPasswordGeneration[];
 extern const char kEnableIOSWKWebView[];
+extern const char kEnableNTPFavicons[];
+extern const char kEnableOfflineAutoReload[];
 extern const char kEnableReaderModeToolbarIcon[];
-extern const char kDisableKeyboardCommands[];
+extern const char kEnableTabSwitcher[];
+
 extern const char kIOSMetricsRecordingOnly[];
+extern const char kUserAgent[];
 
 }  // namespace switches