1 files changed, 101 insertions, 0 deletions
diff --git a/chromium/base/android/field_trial_list.cc b/chromium/base/android/field_trial_list.cc
new file mode 100644
index 00000000000..64b1763529b
--- /dev/null
+++ b/chromium/base/android/field_trial_list.cc
@@ -0,0 +1,101 @@
+// Copyright 2014 The Chromium Authors
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include <jni.h>
+
+#include <map>
+#include <string>
+
+#include "base/android/jni_string.h"
+#include "base/base_jni_headers/FieldTrialList_jni.h"
+#include "base/lazy_instance.h"
+#include "base/metrics/field_trial.h"
+#include "base/metrics/field_trial_params.h"
+
+using base::android::ConvertJavaStringToUTF8;
+using base::android::ConvertUTF8ToJavaString;
+using base::android::JavaParamRef;
+using base::android::ScopedJavaLocalRef;
+
+namespace {
+
+// Log trials and their groups on activation, for debugging purposes.
+class TrialLogger : public base::FieldTrialList::Observer {
+ public:
+  TrialLogger() {}
+
+  TrialLogger(const TrialLogger&) = delete;
+  TrialLogger& operator=(const TrialLogger&) = delete;
+
+  void OnFieldTrialGroupFinalized(const std::string& trial_name,
+                                  const std::string& group_name) override {
+    Log(trial_name, group_name);
+  }
+
+  static void Log(const std::string& trial_name,
+                  const std::string& group_name) {
+    // Changes to format of the log message below must be accompanied by
+    // changes to finch smoke tests since they look for this log message
+    // in the logcat.
+    LOG(INFO) << "Active field trial \"" << trial_name
+              << "\" in group \"" << group_name<< '"';
+  }
+
+ protected:
+  ~TrialLogger() override {}
+};
+
+base::LazyInstance<TrialLogger>::Leaky g_trial_logger =
+    LAZY_INSTANCE_INITIALIZER;
+
+}  // namespace
+
+static ScopedJavaLocalRef<jstring> JNI_FieldTrialList_FindFullName(
+    JNIEnv* env,
+    const JavaParamRef<jstring>& jtrial_name) {
+  std::string trial_name(ConvertJavaStringToUTF8(env, jtrial_name));
+  return ConvertUTF8ToJavaString(
+      env, base::FieldTrialList::FindFullName(trial_name));
+}
+
+static jboolean JNI_FieldTrialList_TrialExists(
+    JNIEnv* env,
+    const JavaParamRef<jstring>& jtrial_name) {
+  std::string trial_name(ConvertJavaStringToUTF8(env, jtrial_name));
+  return base::FieldTrialList::TrialExists(trial_name);
+}
+
+static ScopedJavaLocalRef<jstring> JNI_FieldTrialList_GetVariationParameter(
+    JNIEnv* env,
+    const JavaParamRef<jstring>& jtrial_name,
+    const JavaParamRef<jstring>& jparameter_key) {
+  std::map<std::string, std::string> parameters;
+  base::GetFieldTrialParams(ConvertJavaStringToUTF8(env, jtrial_name),
+                            &parameters);
+  return ConvertUTF8ToJavaString(
+      env, parameters[ConvertJavaStringToUTF8(env, jparameter_key)]);
+}
+
+static void JNI_FieldTrialList_LogActiveTrials(JNIEnv* env) {
+  DCHECK(!g_trial_logger.IsCreated()); // This need only be called once.
+
+  LOG(INFO) << "Logging active field trials...";
+  base::FieldTrialList::AddObserver(&g_trial_logger.Get());
+
+  // Log any trials that were already active before adding the observer.
+  std::vector<base::FieldTrial::ActiveGroup> active_groups;
+  base::FieldTrialList::GetActiveFieldTrialGroups(&active_groups);
+  for (const base::FieldTrial::ActiveGroup& group : active_groups) {
+    TrialLogger::Log(group.trial_name, group.group_name);
+  }
+}
+
+static jboolean JNI_FieldTrialList_CreateFieldTrial(
+    JNIEnv* env,
+    const JavaParamRef<jstring>& jtrial_name,
+    const JavaParamRef<jstring>& jgroup_name) {
+  return base::FieldTrialList::CreateFieldTrial(
+             ConvertJavaStringToUTF8(env, jtrial_name),
+             ConvertJavaStringToUTF8(env, jgroup_name)) != nullptr;
+}