[ios] Workaround error affecting 3rd party keyboards and omnibox.

ios/chrome/browser/experimental_flags.mm

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This file can be empty. Its purpose is to contain the relatively short lived
 // definitions required for experimental flags.
 
 #include "ios/chrome/browser/experimental_flags.h"
 
 #include <dispatch/dispatch.h>
@@ skipping 26 matching lines @@
 NSString* const kForceResetContextualSearch = @"ForceResetContextualSearch";
 NSString* const kGaiaEnvironment = @"GAIAEnvironment";
 NSString* const kHeuristicsForPasswordGeneration =
     @"HeuristicsForPasswordGeneration";
 NSString* const kMDMIntegrationDisabled = @"MDMIntegrationDisabled";
 NSString* const kOriginServerHost = @"AlternateOriginServerHost";
 NSString* const kSafariVCSignInDisabled = @"SafariVCSignInDisabled";
 NSString* const kWhatsNewPromoStatus = @"WhatsNewPromoStatus";
 const base::Feature kEnableSlimNavigationManager{
     "EnableSlimNavigationManager", base::FEATURE_DISABLED_BY_DEFAULT};
+const base::Feature kEnableThirdPartyKeyboardWorkaround{
+    "EnableThirdPartyKeyboardWorkaround", base::FEATURE_ENABLED_BY_DEFAULT};
 
 }  // namespace
 
 namespace experimental_flags {
 
 bool AlwaysDisplayFirstRun() {
   return
       [[NSUserDefaults standardUserDefaults] boolForKey:kFirstRunForceEnabled];
 }
 
@@ skipping 240 matching lines @@
   if (command_line->HasSwitch(switches::kEnableSlimNavigationManager)) {
     return true;
   } else if (command_line->HasSwitch(switches::kDisableSlimNavigationManager)) {
     return false;
   }
 
   // Check if the Finch experiment is turned on.
   return base::FeatureList::IsEnabled(kEnableSlimNavigationManager);
 }
 
+bool IsThirdPartyKeyboardWorkaroundEnabled() {
+  // Check if the experimental flag is forced on or off.
+  base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
+  if (command_line->HasSwitch(switches::kEnableThirdPartyKeyboardWorkaround)) {
+    return true;
+  } else if (command_line->HasSwitch(
+                 switches::kDisableThirdPartyKeyboardWorkaround)) {
+    return false;
+  }
+
+  // Check if the Finch experiment is turned on.
+  return base::FeatureList::IsEnabled(kEnableThirdPartyKeyboardWorkaround);
+}
+
 }  // namespace experimental_flags