Adds support for OpenSL ES based audio capture on Android

webrtc/modules/audio_device/android/build_info.h

 /*
  *  Copyright (c) 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.
  */
 
 #ifndef WEBRTC_MODULES_AUDIO_DEVICE_ANDROID_BUILD_INFO_H_
 #define WEBRTC_MODULES_AUDIO_DEVICE_ANDROID_BUILD_INFO_H_
 
 #include <jni.h>
 #include <memory>
 #include <string>
 
 #include "webrtc/modules/utility/include/jvm_android.h"
 
 namespace webrtc {
 
+// This enumeration maps to the values returned by BuildInfo::GetSdkVersion(),
+// indicating the Android release associated with a given SDK version.
+// See https://developer.android.com/guide/topics/manifest/uses-sdk-element.html
+// for details.
+enum SdkCode {
+  SDK_CODE_JELLY_BEAN = 16,      // Android 4.1
+  SDK_CODE_JELLY_BEAN_MR1 = 17,  // Android 4.2
+  SDK_CODE_JELLY_BEAN_MR2 = 18,  // Android 4.3
+  SDK_CODE_KITKAT = 19,          // Android 4.4
+  SDK_CODE_WATCH = 20,           // Android 4.4W
+  SDK_CODE_LOLLIPOP = 21,        // Android 5.0
+  SDK_CODE_LOLLIPOP_MR1 = 22,    // Android 5.1
+  SDK_CODE_MARSHMALLOW = 23,     // Android 6.0
+  SDK_CODE_N = 24,
+};
+
 // Utility class used to query the Java class (org/webrtc/voiceengine/BuildInfo)
 // for device and Android build information.
 // The calling thread is attached to the JVM at construction if needed and a
 // valid Java environment object is also created.
 // All Get methods must be called on the creating thread. If not, the code will
 // hit RTC_DCHECKs when calling JNIEnvironment::JavaToStdString().
 class BuildInfo {
  public:
   BuildInfo();
   ~BuildInfo() {}
 
   // End-user-visible name for the end product (e.g. "Nexus 6").
   std::string GetDeviceModel();
   // Consumer-visible brand (e.g. "google").
   std::string GetBrand();
   // Manufacturer of the product/hardware (e.g. "motorola").
   std::string GetDeviceManufacturer();
   // Android build ID (e.g. LMY47D).
   std::string GetAndroidBuildId();
   // The type of build (e.g. "user" or "eng").
   std::string GetBuildType();
   // The user-visible version string (e.g. "5.1").
   std::string GetBuildRelease();
-  // The user-visible SDK version of the framework (e.g. 21).
-  std::string GetSdkVersion();
+  // The user-visible SDK version of the framework (e.g. 21). See SdkCode enum
+  // for translation.
+  SdkCode GetSdkVersion();
 
  private:
   // Helper method which calls a static getter method with |name| and returns
   // a string from Java.
   std::string GetStringFromJava(const char* name);
 
   // Ensures that this class can access a valid JNI interface pointer even
   // if the creating thread was not attached to the JVM.
   AttachCurrentThreadIfNeeded attach_thread_if_needed_;
 
   // Provides access to the JNIEnv interface pointer and the JavaToStdString()
   // method which is used to translate Java strings to std strings.
   std::unique_ptr<JNIEnvironment> j_environment_;
 
   // Holds the jclass object and provides access to CallStaticObjectMethod().
   // Used by GetStringFromJava() during construction only.
   JavaClass j_build_info_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_MODULES_AUDIO_DEVICE_ANDROID_BUILD_INFO_H_