Update libwebrtc to use dist_jar instead of custom java8_dist_jar.

The custom template seems to be broken. The necessary flag
"use_unprocessed_jars" has been added to dist_jar template and the
custom template is not needed anymore.

Bug: None
Change-Id: I0ca7a91ee47c8de659bcaffa5661bff55af50375
Reviewed-on: https://webrtc-review.googlesource.com/42680
Reviewed-by: Anders Carlsson <andersc@webrtc.org>
Commit-Queue: Sami Kalliomäki <sakal@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21721}

sdk/android/BUILD.gn

@@ -515,61 +515,12 @@ rtc_shared_library("libjingle_peerconnection_so") {
   output_extension = "so"
 }
 
-template("java8_dist_jar") {
+dist_jar("libwebrtc") {
-  _deps = []
-  _output_jars = []
-  foreach(dep, invoker.deps) {
-    _dep_name = get_label_info(dep, "name")
-    _source_jar =
-        get_label_info(dep, "target_gen_dir") + "/" + _dep_name + ".javac.jar"
-    _output_jar = "$target_gen_dir/" + _dep_name + ".jar"
-
-    _copy_target_name = "${target_name}_${_dep_name}_copy"
-
-    copy(_copy_target_name) {
-      sources = [
-        _source_jar,
-      ]
-      outputs = [
-        _output_jar,
-      ]
-      deps = [
-        dep,
-      ]
-    }
-    _deps += [ ":" + _copy_target_name ]
-    _output_jars += [ _output_jar ]
-  }
-
-  action(target_name) {
-    forward_variables_from(invoker, [ "data" ])
-    script = "//build/android/gyp/create_dist_jar.py"
-    depfile = "$target_gen_dir/$target_name.d"
-    deps = _deps
-
-    outputs = [
-      invoker.output,
-    ]
-
-    args = [
-      "--depfile",
-      rebase_path(depfile, root_build_dir),
-      "--output",
-      rebase_path(invoker.output, root_build_dir),
-    ]
-
-    foreach(output_jar, _output_jars) {
-      args += [
-        "--jars",
-        rebase_path(output_jar, root_build_dir),
-      ]
-    }
-  }
-}
-
-java8_dist_jar("libwebrtc") {
   _target_dir_name = get_label_info(":$target_name", "dir")
   output = "${root_out_dir}/lib.java${_target_dir_name}/${target_name}.jar"
+  direct_deps_only = true
+  use_unprocessed_jars = true
+  requires_android = true
 
   deps = [
     ":libjingle_peerconnection_java",