GN: Enable blink and (nearly) all of content in android build

content/public/android/BUILD.gn

 # Copyright 2014 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.
 
 import("//build/config/android/config.gni")
 import("//build/config/android/rules.gni")
 
+content_jni_gypi_values = exec_script("//build/gypi_to_gn.py",
+    [ rebase_path("../../content_jni.gypi") ],
+    "scope",
+    [ "../../content_jni.gypi" ])
+
 android_aidl("common_aidl") {
   interface_file = "java/src/org/chromium/content/common/common.aidl"
   import_include = "java/src"
   sources = [
     "java/src/org/chromium/content/common/IChildProcessCallback.aidl",
     "java/src/org/chromium/content/common/IChildProcessService.aidl",
   ]
 }
 
 android_resources("content_java_resources") {
@@ skipping 175 matching lines @@
     "java/src/org/chromium/content/browser/input/CanonicalAxisIndex.template",
     "java/src/org/chromium/content/browser/input/CanonicalButtonIndex.template",
   ]
   package_name = "org/chromium/content/common"
   inputs = [
     "//content/browser/gamepad/canonical_axis_index_list.h",
     "//content/browser/gamepad/canonical_button_index_list.h",
   ]
 }
 
-generate_jar_jni("content_jni_headers") {
+generate_jar_jni("jar_jni") {
   jni_package = "content"
   classes = [
+    "java/util/HashSet.class",
     "android/view/MotionEvent.class",
-    "java/util/HashSet.class",
   ]
 }
 
+generate_jni("content_jni_headers") {
+  sources = rebase_path(content_jni_gypi_values.sources, "", "../..")
+  jni_package = "content"
+}
+
+group("jni") {
+  deps = [
+    ":content_jni_headers",
+    ":jar_jni",
+  ]
+}
+
 android_library("content_javatests") {
   deps = [
     "//base:base_java",
     "//base:base_java_test_support",
     "//content/public/test/android:content_java_test_support",
     "//content/shell/android:content_shell_java",
     "//content/shell/android:content_shell_apk_java",
     "//content/shell/android:content_shell_test_java",
     "//media/base/android:media_java",
     "//net/android:net_java",
     "//net/android:net_java_test_support",
     "//ui/android:ui_java",
     ":content_java",
   ]
 
   DEPRECATED_java_in_dir = "javatests/src"
 }
 
 
 # TODO(GYP): content_icudata