Revert of Combine webrtc/api/java/android and webrtc/api/java/src. (patchset #1 id:1 of https://codereview.webrtc.org/2111823002/ )

Reason for revert:
Breaks downstream dependencies

Original issue's description:
> Combine webrtc/api/java/android and webrtc/api/java/src.
>
> It used to be that there was a Java api for devices not running Android
> but that is no longer the case. I combined the directories and made
> the folder structure chromium style.
>
> BUG=webrtc:6067
> R=magjed@webrtc.org, tommi@webrtc.org
>
> Committed: https://chromium.googlesource.com/external/webrtc/+/ceefe20dd65387d83059d9fc1ce84842650ed5e2

TBR=magjed@webrtc.org,tommi@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6067

Review URL: https://codereview.webrtc.org/2106333005 .

Cr-Commit-Position: refs/heads/master@{#13357}
diff --git a/webrtc/api/BUILD.gn b/webrtc/api/BUILD.gn
index 8f3327a..b0784ad 100644
--- a/webrtc/api/BUILD.gn
+++ b/webrtc/api/BUILD.gn
@@ -147,27 +147,27 @@
 
   source_set("libjingle_peerconnection_jni") {
     sources = [
-      "android/jni/androidmediacodeccommon.h",
-      "android/jni/androidmediadecoder_jni.cc",
-      "android/jni/androidmediadecoder_jni.h",
-      "android/jni/androidmediaencoder_jni.cc",
-      "android/jni/androidmediaencoder_jni.h",
-      "android/jni/androidmetrics_jni.cc",
-      "android/jni/androidnetworkmonitor_jni.cc",
-      "android/jni/androidnetworkmonitor_jni.h",
-      "android/jni/androidvideocapturer_jni.cc",
-      "android/jni/androidvideocapturer_jni.h",
-      "android/jni/classreferenceholder.cc",
-      "android/jni/classreferenceholder.h",
-      "android/jni/jni_helpers.cc",
-      "android/jni/jni_helpers.h",
-      "android/jni/native_handle_impl.cc",
-      "android/jni/native_handle_impl.h",
-      "android/jni/peerconnection_jni.cc",
-      "android/jni/surfacetexturehelper_jni.cc",
-      "android/jni/surfacetexturehelper_jni.h",
       "androidvideocapturer.cc",
       "androidvideocapturer.h",
+      "java/jni/androidmediacodeccommon.h",
+      "java/jni/androidmediadecoder_jni.cc",
+      "java/jni/androidmediadecoder_jni.h",
+      "java/jni/androidmediaencoder_jni.cc",
+      "java/jni/androidmediaencoder_jni.h",
+      "java/jni/androidmetrics_jni.cc",
+      "java/jni/androidnetworkmonitor_jni.cc",
+      "java/jni/androidnetworkmonitor_jni.h",
+      "java/jni/androidvideocapturer_jni.cc",
+      "java/jni/androidvideocapturer_jni.h",
+      "java/jni/classreferenceholder.cc",
+      "java/jni/classreferenceholder.h",
+      "java/jni/jni_helpers.cc",
+      "java/jni/jni_helpers.h",
+      "java/jni/native_handle_impl.cc",
+      "java/jni/native_handle_impl.h",
+      "java/jni/peerconnection_jni.cc",
+      "java/jni/surfacetexturehelper_jni.cc",
+      "java/jni/surfacetexturehelper_jni.h",
     ]
 
     configs += [
@@ -213,7 +213,7 @@
 
   shared_library("libjingle_peerconnection_so") {
     sources = [
-      "android/jni/jni_onload.cc",
+      "java/jni/jni_onload.cc",
     ]
 
     configs -= [ "//build/config/android:hide_native_jni_exports" ]
@@ -232,51 +232,51 @@
       "../modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioRecord.java",
       "../modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java",
       "../modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java",
-      "android/java/src/org/webrtc/AudioSource.java",
-      "android/java/src/org/webrtc/AudioTrack.java",
-      "android/java/src/org/webrtc/CallSessionFileRotatingLogSink.java",
-      "android/java/src/org/webrtc/Camera1Enumerator.java",
-      "android/java/src/org/webrtc/Camera2Capturer.java",
-      "android/java/src/org/webrtc/Camera2Enumerator.java",
-      "android/java/src/org/webrtc/CameraEnumerationAndroid.java",
-      "android/java/src/org/webrtc/CameraEnumerator.java",
-      "android/java/src/org/webrtc/CameraVideoCapturer.java",
-      "android/java/src/org/webrtc/DataChannel.java",
-      "android/java/src/org/webrtc/EglBase.java",
-      "android/java/src/org/webrtc/EglBase10.java",
-      "android/java/src/org/webrtc/EglBase14.java",
-      "android/java/src/org/webrtc/GlRectDrawer.java",
-      "android/java/src/org/webrtc/GlShader.java",
-      "android/java/src/org/webrtc/GlTextureFrameBuffer.java",
-      "android/java/src/org/webrtc/GlUtil.java",
-      "android/java/src/org/webrtc/IceCandidate.java",
-      "android/java/src/org/webrtc/MediaCodecVideoDecoder.java",
-      "android/java/src/org/webrtc/MediaCodecVideoEncoder.java",
-      "android/java/src/org/webrtc/MediaConstraints.java",
-      "android/java/src/org/webrtc/MediaSource.java",
-      "android/java/src/org/webrtc/MediaStream.java",
-      "android/java/src/org/webrtc/MediaStreamTrack.java",
-      "android/java/src/org/webrtc/Metrics.java",
-      "android/java/src/org/webrtc/NetworkMonitor.java",
-      "android/java/src/org/webrtc/NetworkMonitorAutoDetect.java",
-      "android/java/src/org/webrtc/PeerConnection.java",
-      "android/java/src/org/webrtc/PeerConnectionFactory.java",
-      "android/java/src/org/webrtc/RendererCommon.java",
-      "android/java/src/org/webrtc/RtpParameters.java",
-      "android/java/src/org/webrtc/RtpReceiver.java",
-      "android/java/src/org/webrtc/RtpSender.java",
-      "android/java/src/org/webrtc/SdpObserver.java",
-      "android/java/src/org/webrtc/SessionDescription.java",
-      "android/java/src/org/webrtc/StatsObserver.java",
-      "android/java/src/org/webrtc/StatsReport.java",
-      "android/java/src/org/webrtc/SurfaceTextureHelper.java",
-      "android/java/src/org/webrtc/SurfaceViewRenderer.java",
-      "android/java/src/org/webrtc/VideoCapturer.java",
-      "android/java/src/org/webrtc/VideoCapturerAndroid.java",
-      "android/java/src/org/webrtc/VideoRenderer.java",
-      "android/java/src/org/webrtc/VideoRendererGui.java",
-      "android/java/src/org/webrtc/VideoSource.java",
-      "android/java/src/org/webrtc/VideoTrack.java",
+      "java/android/org/webrtc/Camera1Enumerator.java",
+      "java/android/org/webrtc/Camera2Capturer.java",
+      "java/android/org/webrtc/Camera2Enumerator.java",
+      "java/android/org/webrtc/CameraEnumerationAndroid.java",
+      "java/android/org/webrtc/CameraEnumerator.java",
+      "java/android/org/webrtc/CameraVideoCapturer.java",
+      "java/android/org/webrtc/EglBase.java",
+      "java/android/org/webrtc/EglBase10.java",
+      "java/android/org/webrtc/EglBase14.java",
+      "java/android/org/webrtc/GlRectDrawer.java",
+      "java/android/org/webrtc/GlShader.java",
+      "java/android/org/webrtc/GlTextureFrameBuffer.java",
+      "java/android/org/webrtc/GlUtil.java",
+      "java/android/org/webrtc/NetworkMonitor.java",
+      "java/android/org/webrtc/NetworkMonitorAutoDetect.java",
+      "java/android/org/webrtc/RendererCommon.java",
+      "java/android/org/webrtc/SurfaceTextureHelper.java",
+      "java/android/org/webrtc/SurfaceViewRenderer.java",
+      "java/android/org/webrtc/VideoCapturerAndroid.java",
+      "java/android/org/webrtc/VideoRendererGui.java",
+      "java/src/org/webrtc/AudioSource.java",
+      "java/src/org/webrtc/AudioTrack.java",
+      "java/src/org/webrtc/CallSessionFileRotatingLogSink.java",
+      "java/src/org/webrtc/DataChannel.java",
+      "java/src/org/webrtc/IceCandidate.java",
+      "java/src/org/webrtc/MediaCodecVideoDecoder.java",
+      "java/src/org/webrtc/MediaCodecVideoEncoder.java",
+      "java/src/org/webrtc/MediaConstraints.java",
+      "java/src/org/webrtc/MediaSource.java",
+      "java/src/org/webrtc/MediaStream.java",
+      "java/src/org/webrtc/MediaStreamTrack.java",
+      "java/src/org/webrtc/Metrics.java",
+      "java/src/org/webrtc/PeerConnection.java",
+      "java/src/org/webrtc/PeerConnectionFactory.java",
+      "java/src/org/webrtc/RtpParameters.java",
+      "java/src/org/webrtc/RtpReceiver.java",
+      "java/src/org/webrtc/RtpSender.java",
+      "java/src/org/webrtc/SdpObserver.java",
+      "java/src/org/webrtc/SessionDescription.java",
+      "java/src/org/webrtc/StatsObserver.java",
+      "java/src/org/webrtc/StatsReport.java",
+      "java/src/org/webrtc/VideoCapturer.java",
+      "java/src/org/webrtc/VideoRenderer.java",
+      "java/src/org/webrtc/VideoSource.java",
+      "java/src/org/webrtc/VideoTrack.java",
     ]
 
     deps = [