Relanding: Break peerconnection_jni.cc into multiple files, in "pc" directory.

webrtc/sdk/android/src/jni/jni_helpers.cc

 /*
  *  Copyright 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 #include "webrtc/sdk/android/src/jni/jni_helpers.h"
@@ skipping 255 matching lines @@
   jmethodID state_values_id = GetStaticMethodID(
       jni, state_class, "values", ("()[L" + state_class_name  + ";").c_str());
   jobjectArray state_values = static_cast<jobjectArray>(
       jni->CallStaticObjectMethod(state_class, state_values_id));
   CHECK_EXCEPTION(jni) << "error during CallStaticObjectMethod";
   jobject ret = jni->GetObjectArrayElement(state_values, index);
   CHECK_EXCEPTION(jni) << "error during GetObjectArrayElement";
   return ret;
 }
 
+jobject JavaEnumFromIndexAndClassName(JNIEnv* jni,
+                                      const std::string& state_class_fragment,
+                                      int index) {
+  const std::string state_class = "org/webrtc/" + state_class_fragment;
+  return JavaEnumFromIndex(jni, FindClass(jni, state_class.c_str()),
+                           state_class, index);
+}
+
 std::string GetJavaEnumName(JNIEnv* jni,
                             const std::string& className,
                             jobject j_enum) {
   jclass enumClass = FindClass(jni, className.c_str());
   jmethodID nameMethod =
       GetMethodID(jni, enumClass, "name", "()Ljava/lang/String;");
   jstring name =
       reinterpret_cast<jstring>(jni->CallObjectMethod(j_enum, nameMethod));
   CHECK_EXCEPTION(jni) << "error during CallObjectMethod for " << className
                        << ".name";
@@ skipping 85 matching lines @@
   RTC_CHECK(!AtEnd());
   return value_;
 }
 
 bool Iterable::Iterator::AtEnd() const {
   RTC_CHECK(thread_checker_.CalledOnValidThread());
   return jni_ == nullptr || IsNull(jni_, iterator_);
 }
 
 }  // namespace webrtc_jni