[AppRemoting] Break out AppRemoting shared module (re-land).

remoting/app_remoting_webapp_build.gypi

Index: remoting/app_remoting_webapp_build.gypi
diff --git a/remoting/app_remoting_webapp_build.gypi b/remoting/app_remoting_webapp_build.gypi
index bc6ffa6b662d32106a4ae86582f23e4dedb0407f..50fb6d3d9d12e4765f142a27c084e299ff22a8ec 100644
--- a/remoting/app_remoting_webapp_build.gypi
+++ b/remoting/app_remoting_webapp_build.gypi
@@ -40,18 +40,10 @@
         '>(ar_app_path)/icon128.png',
         '>(ar_app_path)/loading_splash.png',
       ],
-      'ar_generated_html_files': [
-        '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/loading_window.html',
-        '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/main.html',
-        '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/message_window.html',
-        '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/wcs_sandbox.html',
-        '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/feedback_consent.html',
-      ],
       'ar_webapp_files': [
         '<@(ar_app_specific_files)',
-        '<@(ar_shared_resource_files)',
-        '<@(ar_all_js_files)',
-        '<@(ar_generated_html_files)',
+        '<@(ar_vendor_js_files)',
+        '<@(ar_vendor_html_files)',
       ],
       'output_dir': '<(PRODUCT_DIR)/app_streaming/<@(ar_service_environment)/>(_target_name)',
       'zip_path': '<(PRODUCT_DIR)/app_streaming/<@(ar_service_environment)/>(_target_name).zip',
@@ -102,7 +94,6 @@
           '<(remoting_version_path)',
           '<@(ar_webapp_files)',
           '<@(remoting_webapp_locale_files)',
-          '<@(ar_generated_html_files)',
           '<(ar_app_manifest_app)',
           '<(DEPTH)/remoting/<(ar_app_manifest_common)',
           '<(ar_webapp_locales_listfile)',
@@ -162,6 +153,25 @@
         ],
       },
       {
+        'action_name': 'Build ">(ar_app_name)" ar_background.html',
+        'inputs': [
+          '<(DEPTH)/remoting/webapp/build-html.py',
+          '<(ar_background_template)',
+        ],
+        'outputs': [
+          '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/ar_background.html',
+        ],
+        'action': [
+          'python', '<(DEPTH)/remoting/webapp/build-html.py',
+          '<(SHARED_INTERMEDIATE_DIR)/>(_target_name)/ar_background.html',
+          '<(ar_background_template)',
+          '--template-dir',
+          '<(DEPTH)/remoting',
+          '--js',
+          '<@(ar_background_html_js_files)',
+        ],
+      },
+      {
         'action_name': 'Build ">(ar_app_name)" wcs_sandbox.html',
         'inputs': [
           '<(DEPTH)/remoting/webapp/build-html.py',