Remove som GYP annotations, remove unused manifest.

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")
 
 android_aidl("common_aidl") {
   interface_file = "java/src/org/chromium/content/common/common.aidl"
   import_include = "java/src"
@@ skipping 410 matching lines @@
 
   data = [
     "//content/test/data/android/",
     "//content/test/data/media/session/",
   ]
   data_deps = [
     "//net:test_support",
   ]
 }
 
-# GYP: //content/content_tests.gypi:content_junit_tests
 junit_binary("content_junit_tests") {
   java_files = [
     "junit/src/org/chromium/content/browser/input/RangeTest.java",
     "junit/src/org/chromium/content/browser/input/TextInputStateTest.java",
     "junit/src/org/chromium/content/browser/input/ThreadedInputConnectionFactoryTest.java",
     "junit/src/org/chromium/content/browser/input/ThreadedInputConnectionTest.java",
     "junit/src/org/chromium/content/browser/BindingManagerImplTest.java",
   ]
   deps = [
     ":content_java",
     "//base:base_java",
     "//base:base_java_test_support",
   ]
 }