Refactor the atom_js2c target to include javascript from multiple dirs.

Before invoking js2c, copy all files that must be embedded into the shared
intermediate directory, and modify the js2c wrapper script to include all files
from that directory(which is passed as argument).

This allows the build system to embed files that don't share a common base
directory, such as javascript generated at build time.

electron.gyp

@@ -5,6 +5,7 @@
     'company_name%': 'GitHub, Inc',
     'company_abbr%': 'github',
     'version%': '1.4.1',
+    'js2c_input_dir': '<(SHARED_INTERMEDIATE_DIR)/js2c',
   },
   'includes': [
     'filenames.gypi',
@@ -410,13 +411,29 @@
         }
       ],
     },  # target app2asar
+    {
+      'target_name': 'atom_js2c_copy',
+      'type': 'none',
+      'copies': [
+        {
+          'destination': '<(js2c_input_dir)',
+          'files': [
+            '<@(js2c_sources)',
+          ],
+        },
+      ],
+    },  # target atom_js2c_copy
     {
       'target_name': 'atom_js2c',
       'type': 'none',
+      'dependencies': [
+        'atom_js2c_copy',
+      ],
       'actions': [
         {
           'action_name': 'atom_js2c',
           'inputs': [
+            # List all input files that should trigger a rebuild with js2c
             '<@(js2c_sources)',
           ],
           'outputs': [
@@ -426,7 +443,7 @@
             'python',
             'tools/js2c.py',
             '<@(_outputs)',
-            '<@(_inputs)',
+            '<(js2c_input_dir)',
           ],
         }
       ],

tools/js2c.py

@@ -1,6 +1,7 @@
 #!/usr/bin/env python
 
 import contextlib
+import glob
 import os
 import subprocess
 import sys
@@ -11,7 +12,7 @@ SOURCE_ROOT = os.path.abspath(os.path.dirname(os.path.dirname(__file__)))
 
 def main():
   natives = os.path.abspath(sys.argv[1])
-  js_source_files = sys.argv[2:]
+  js_source_files = glob.glob('{0}/*.js'.format(sys.argv[2]))
 
   call_js2c(natives, js_source_files)