Android: Add pseudo module for Android Studio

build/android/gradle/android.jinja

 {# Copyright 2016 The Chromium Authors. All rights reserved. #}
 {# Use of this source code is governed by a BSD-style license that can be #}
 {# found in the LICENSE file. #}
 {% macro expand_sourceset(variables, prefix) %}
 {% if variables is defined %}
         {{ prefix }} {
             manifest.srcFile "{{ variables.android_manifest }}"
+{% if variables.java_dirs is defined %}
             java.srcDirs = [
 {% for path in variables.java_dirs %}
                 "{{ path }}",
 {% endfor %}
             ]
-{% if variables.java_excludes %}
+{% endif %}
+{% if variables.java_excludes is defined %}
             java.filter.exclude(
 {% for path in variables.java_excludes %}
                 "{{ path }}",
 {% endfor %}
             )
 {% endif %}
+{% if variables.jniLibs is defined %}

[sakal-chromium, 2017/05/04 09:37:39]

Should be jni_libs not jniLibs.

[Peter Wen, 2017/05/04 10:19:58]

+1 will fix in follow-up CL.

             jniLibs.srcDirs = [
 {% for path in variables.jni_libs %}
                 "{{ path }}",
 {% endfor %}
             ]
+{% endif %}
+{% if variables.res_dirs is defined %}
             res.srcDirs = [
 {% for path in variables.res_dirs %}
                 "{{ path }}",
 {% endfor %}
             ]
+{% endif %}
         }
 {% endif %}
 {% endmacro %}
 // Generated by //build/android/generate_gradle.py
 
 {% if template_type in ('android_library', 'android_junit') %}
 apply plugin: "com.android.library"
 {% elif template_type == 'android_apk' %}
 apply plugin: "com.android.application"
 {% endif %}
@@ skipping 53 matching lines @@
     }
     tasksToDisable.each { Task task ->
       task.enabled = false
     }
 {% if bootclasspath is defined %}
     tasks.withType(JavaCompile) {
       options.bootClasspath = "{{ bootclasspath }}"
     }
 {% endif %}
 }