Reland of Fixing package-boundary violation with srjar_deps (patchset #1 id:1 of https://codereview.webrtc.org/2617533005/ )

Reason for revert:
Skipping the build of the target "//webrtc/modules/audio_device:audio_device_java" when building webrtc with chromium.

This was causing a failure because in that case it is not possible to refer to the script used by the template "android_shared_srcjar" with an absolute path (which seems to be necessary since the script attribute of action is relative to the invocation target and not to the template declaration).

Original issue's description:
> Revert of Fixing package-boundary violation with srjar_deps (patchset #5 id:80001 of https://codereview.webrtc.org/2610823002/ )
>
> Reason for revert:
> This CL is breaking a chromium.webrtc.fyi: https://build.chromium.org/p/chromium.webrtc.fyi/builders/Android%20Builder/builds/226
>
> I am trying to reproduce the issue on my local machine and I will try to re-land the CL later.
>
> Original issue's description:
> > Fixing package-boundary violation with srjar_deps
> >
> > Without the usage of the srcjar_deps attribute we were not able to
> > include .java files from other packages without violating the package
> > boundary contraint.
> >
> > As an example, in this CL the target "libjingle_peerconnection_java" was
> > directly including .java files from another packages in its "java_files"
> > attribute.
> >
> > Using srcjar_deps we are able to declare the dependency of the target
> > avoiding to create hidden dependencies in the codebase.
> >
> > This is not fixing the webrtc:6356 bug directly but it is a first step to
> > include ThreadUtils classes in libjingle_peerconnection_client_java.jar
> > again.
> >
> > It seems also to be related to the chromium:648244 bug. This can be solved
> > if we can find a way to perform srcjar generation in the android_library
> > target without changing the semantic of the target.
> >
> > BUG=webrtc:6356
> >
> > Review-Url: https://codereview.webrtc.org/2610823002
> > Cr-Commit-Position: refs/heads/master@{#15914}
> > Committed: 10a76592a7
>
> TBR=kjellander@webrtc.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
> BUG=webrtc:6356
>
> Review-Url: https://codereview.webrtc.org/2617533005
> Cr-Commit-Position: refs/heads/master@{#15915}
> Committed: eb731ed09e

TBR=kjellander@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6356

Review-Url: https://codereview.webrtc.org/2612953004
Cr-Commit-Position: refs/heads/master@{#15958}

webrtc/build/generate_srcjar.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python
+#
+# Copyright (c) 2017 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.
+
+# TODO(mbonadei): move this script into chromium (build/android/gyp)
+# when approved
+
+import optparse
+import os
+import re
+import sys
+import zipfile
+
+sys.path.insert(0, os.path.abspath(os.path.join(os.pardir, os.pardir, 'build',
+                                                'android', 'gyp', 'util')))
+import build_utils
+
+
+def PackageToPath(src_file):
+  """Returns the path of a .java file according to the package declaration.
+
+  Example:
+  src_file='/home/foo/bar/org/android/TestClass.java'
+  With the following package definition:
+  package org.android;
+
+  It will return 'org/android'.
+
+  Args:
+    A string with the path of the .java source file to analyze.
+
+  Returns:
+    A string with the translation of the package definition into a path.
+  """
+  with open(src_file) as f:
+    file_src = f.read()
+    package = re.search('package (.*);', file_src).group(1)
+    zip_folder = package.replace('.', os.path.sep)
+    file_name = os.path.basename(src_file)
+    return os.path.join(zip_folder, file_name)
+
+
+def DoMain(argv):
+  usage = 'usage: %prog [options] input_file(s)...'
+  parser = optparse.OptionParser(usage=usage)
+  parser.add_option('-s', '--srcjar',
+                    help='The path where the .srcjar file will be generated')
+
+  options, args = parser.parse_args(argv)
+
+  if not args:
+    parser.error('Need to specify at least one input source file (.java)')
+  input_paths = args
+
+  with zipfile.ZipFile(options.srcjar, 'w', zipfile.ZIP_STORED) as srcjar:
+    for src_path in input_paths:
+      zip_path = PackageToPath(src_path)
+      build_utils.AddToZipHermetic(srcjar, zip_path, src_path)
+
+
+if __name__ == '__main__':
+  DoMain(sys.argv[1:])

webrtc/build/webrtc.gni

@@ -324,3 +324,32 @@ template("rtc_shared_library") {
     }
   }
 }
+
+# TODO(mbonadei): Merge this in android_library or create an
+# rtc_android_library. Waiting for hints from chromium:648244.
+if (is_android) {
+  template("android_shared_srcjar") {
+    action(target_name) {
+      check_includes = false
+      set_sources_assignment_filter([])
+      assert(defined(invoker.sources))
+
+      forward_variables_from(invoker,
+                             [
+                               "sources",
+                               "testonly",
+                               "visibility",
+                             ])
+      script = "//webrtc/build/generate_srcjar.py"
+      _srcjar_path = "${target_gen_dir}/${target_name}.srcjar"
+      _rebased_srcjar_path = rebase_path(_srcjar_path, root_build_dir)
+      _rebased_sources = rebase_path(invoker.sources, root_build_dir)
+
+      args = [ "--srcjar=$_rebased_srcjar_path" ] + _rebased_sources
+
+      outputs = [
+        _srcjar_path,
+      ]
+    }
+  }
+}

webrtc/modules/audio_device/BUILD.gn

@@ -8,6 +8,11 @@
 
 import("../../build/webrtc.gni")
 
+if (is_android) {
+  import("//build/config/android/config.gni")
+  import("//build/config/android/rules.gni")
+}
+
 config("audio_device_config") {
   include_dirs = [
     "../include",
@@ -296,3 +301,16 @@ if (rtc_include_tests && !is_ios) {
     public_configs = [ ":audio_device_config" ]
   }
 }
+
+if (!build_with_chromium && is_android) {
+  android_shared_srcjar("audio_device_java") {
+    sources = [
+      "android/java/src/org/webrtc/voiceengine/BuildInfo.java",
+      "android/java/src/org/webrtc/voiceengine/WebRtcAudioEffects.java",
+      "android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java",
+      "android/java/src/org/webrtc/voiceengine/WebRtcAudioRecord.java",
+      "android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java",
+      "android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java",
+    ]
+  }
+}

webrtc/sdk/android/BUILD.gn

@@ -112,12 +112,6 @@ rtc_shared_library("libjingle_peerconnection_so") {
 
 android_library("libjingle_peerconnection_java") {
   java_files = [
-    "//webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/BuildInfo.java",
-    "//webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioEffects.java",
-    "//webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioManager.java",
-    "//webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioRecord.java",
-    "//webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioTrack.java",
-    "//webrtc/modules/audio_device/android/java/src/org/webrtc/voiceengine/WebRtcAudioUtils.java",
     "api/org/webrtc/AudioSource.java",
     "api/org/webrtc/AudioTrack.java",
     "api/org/webrtc/CallSessionFileRotatingLogSink.java",
@@ -178,6 +172,8 @@ android_library("libjingle_peerconnection_java") {
   deps = [
     "//webrtc/base:base_java",
   ]
+
+  srcjar_deps = [ "//webrtc/modules/audio_device:audio_device_java" ]
 }
 
 android_library("libjingle_peerconnection_metrics_default_java") {