Add support for calling the java Callback from native.

base/BUILD.gn

 # Copyright (c) 2013 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.
 
 # HOW TO WRITE CONDITIONALS IN THIS FILE
 # ======================================
 #
 # In many other places, one would write a conditional that expresses all the
 # cases when a source file is used or unused, and then either add or subtract
 # it from the sources list in that case
@@ skipping 130 matching lines @@
     "android/apk_assets.cc",
     "android/apk_assets.h",
     "android/application_status_listener.cc",
     "android/application_status_listener.h",
     "android/base_jni_onload.cc",
     "android/base_jni_onload.h",
     "android/base_jni_registrar.cc",
     "android/base_jni_registrar.h",
     "android/build_info.cc",
     "android/build_info.h",
+    "android/callback_android.cc",
+    "android/callback_android.h",
     "android/command_line_android.cc",
     "android/command_line_android.h",
     "android/content_uri_utils.cc",
     "android/content_uri_utils.h",
     "android/context_utils.cc",
     "android/context_utils.h",
     "android/cpu_features.cc",
     "android/cxa_demangle_stub.cc",
     "android/event_log.cc",
     "android/event_log.h",
@@ skipping 1964 matching lines @@
 }
 
 if (is_android) {
   # GYP: //base.gyp:base_jni_headers
   generate_jni("base_jni_headers") {
     sources = [
       "android/java/src/org/chromium/base/AnimationFrameTimeHistogram.java",
       "android/java/src/org/chromium/base/ApkAssets.java",
       "android/java/src/org/chromium/base/ApplicationStatus.java",
       "android/java/src/org/chromium/base/BuildInfo.java",
+      "android/java/src/org/chromium/base/Callback.java",
       "android/java/src/org/chromium/base/CommandLine.java",
       "android/java/src/org/chromium/base/ContentUriUtils.java",
       "android/java/src/org/chromium/base/ContextUtils.java",
       "android/java/src/org/chromium/base/CpuFeatures.java",
       "android/java/src/org/chromium/base/EventLog.java",
       "android/java/src/org/chromium/base/FieldTrialList.java",
       "android/java/src/org/chromium/base/ImportantFileWriterAndroid.java",
       "android/java/src/org/chromium/base/JNIUtils.java",
       "android/java/src/org/chromium/base/JavaHandlerThread.java",
       "android/java/src/org/chromium/base/LocaleUtils.java",
@@ skipping 228 matching lines @@
 
   # GYP: //base.gyp:base_java_unittest_support
   android_library("base_java_unittest_support") {
     deps = [
       ":base_java",
     ]
     java_files =
         [ "test/android/java/src/org/chromium/base/ContentUriTestUtils.java" ]
   }
 }