Update from https://crrev.com/303153

base/android/field_trial_list.cc

 // Copyright 2014 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.
 
 #include "base/android/field_trial_list.h"
 
 #include <jni.h>
 
 #include "base/android/jni_string.h"
 #include "base/metrics/field_trial.h"
 #include "jni/FieldTrialList_jni.h"
 
 using base::android::ConvertJavaStringToUTF8;
 using base::android::ConvertUTF8ToJavaString;
 
 static jstring FindFullName(JNIEnv* env,
                             jclass clazz,
                             jstring jtrial_name) {
   std::string trial_name(ConvertJavaStringToUTF8(env, jtrial_name));
   return ConvertUTF8ToJavaString(
       env,
       base::FieldTrialList::FindFullName(trial_name)).Release();
 }
 
+static jboolean TrialExists(JNIEnv* env, jclass clazz, jstring jtrial_name) {
+  std::string trial_name(ConvertJavaStringToUTF8(env, jtrial_name));
+  return base::FieldTrialList::TrialExists(trial_name);
+}
+
 namespace base {
 namespace android {
 
 bool RegisterFieldTrialList(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace android
 }  // namespace base