PDF Plugin: Add compile targets for a few files.

chrome/browser/resources/pdf/compiled_resources2.gyp

 # Copyright 2017 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.
+
+# TODO(dpapad): Add compile targets for all files, crbug.com/721073.
 {
   'targets': [
     {
-      'target_name': 'main',
+      'target_name': 'gesture_detector',
+      'includes': ['../../../../third_party/closure_compiler/compile_js2.gypi'],
+    },
+    {
+      'target_name': 'open_pdf_params_parser',
+      'includes': ['../../../../third_party/closure_compiler/compile_js2.gypi'],
+    },
+    {
+      'target_name': 'pdf_scripting_api',
       'dependencies': [
-        # TODO(dpapad): Add dependencies here.
+        '<(DEPTH)/ui/webui/resources/js/compiled_resources2.gyp:assert',
       ],
       'includes': ['../../../../third_party/closure_compiler/compile_js2.gypi'],
-    }
+    },
+    {
+      'target_name': 'viewport_scroller',
+      'includes': ['../../../../third_party/closure_compiler/compile_js2.gypi'],
+    },
   ],
 }