Reland of Combine webrtc/api/java/android and webrtc/api/java/src. (patchset #1 id:1 of https://codereview.webrtc.org/2106333005/ )

Reason for revert:
Issues fixed

Original issue's description:
> 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: ceefe20dd6
>
> 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
>
> Committed: 9b0dc622d4

TBR=magjed@webrtc.org,tommi@webrtc.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6067

Review-Url: https://codereview.webrtc.org/2111923003
Cr-Commit-Position: refs/heads/master@{#13363}

webrtc/api/api_java.gyp

@@ -34,14 +34,12 @@
             'android_manifest_path': '<(webrtc_root)/build/android/AndroidManifest.xml',
             'suppressions_file': '<(webrtc_root)/build/android/suppressions.xml',
             'chromium_code': 1,
-            'java_in_dir': 'java',
+            'java_in_dir': 'android/java',
             'webrtc_base_dir': '<(webrtc_root)/base',
             'webrtc_modules_dir': '<(webrtc_root)/modules',
             'additional_src_dirs' : [
-              'java/android',
-              '<(webrtc_base_dir)/java/src',
+              '<(webrtc_base_dir)/java',
               '<(webrtc_modules_dir)/audio_device/android/java/src',
-
             ],
           },
           'includes': ['../../build/java.gypi'],