Adds support for OpenSL ES based audio capture on Android

webrtc/modules/audio_device/android/build_info.h

Index: webrtc/modules/audio_device/android/build_info.h
diff --git a/webrtc/modules/audio_device/android/build_info.h b/webrtc/modules/audio_device/android/build_info.h
index 4a4c30e836bab44a5b5e523d2be80ad4e5ecdd5f..d9640dd7bf13a455f43f89a0643ec4f36c1dd168 100644
--- a/webrtc/modules/audio_device/android/build_info.h
+++ b/webrtc/modules/audio_device/android/build_info.h
@@ -19,6 +19,22 @@
 
 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
@@ -42,8 +58,9 @@ class BuildInfo {
   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