Add missing .h files to .gn files that have a .cc file next to it in the gn file already.

ppapi/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/features.gni")
 import("//build/config/nacl/config.gni")
 import("//build/config/nacl/rules.gni")
 import("//ppapi/features/features.gni")
 import("//testing/test.gni")
 if (is_mac) {
@@ skipping 422 matching lines @@
 
   if (is_nacl) {
     nacl_test_data("ppapi_nacl_tests") {
       include_dirs = [ "lib/gl/include" ]
       sources = test_common_source_files
 
       sources += [
         "tests/test_nacl_irt_stack_alignment.cc",
         "tests/test_nacl_irt_stack_alignment.h",
         "tests/test_tcp_server_socket_private_disallowed.cc",
+        "tests/test_tcp_server_socket_private_disallowed.h",
         "tests/test_tcp_socket_private_disallowed.cc",
+        "tests/test_tcp_socket_private_disallowed.h",
         "tests/test_udp_socket_private_disallowed.cc",
+        "tests/test_udp_socket_private_disallowed.h",
       ]
 
       defines = [
         "GL_GLEXT_PROTOTYPES",
         "PPAPI_TEST_IMPLEMENTATION",
       ]
       deps = [
         "//ppapi/cpp",
       ]
       if (current_cpu == "pnacl") {
@@ skipping 13 matching lines @@
       data_deps +=
           [ ":ppapi_nacl_tests(//build/toolchain/nacl:glibc_${target_cpu})" ]
     }
 
     if (is_linux && enable_nacl_nonsfi) {
       data_deps +=
           [ ":ppapi_nacl_tests(//build/toolchain/nacl:newlib_pnacl_nonsfi)" ]
     }
   }
 }