Load application manifests from resources

mojo/public/tools/manifest/manifest_collator.py

Index: mojo/public/tools/manifest/manifest_collator.py
diff --git a/mojo/public/tools/manifest/manifest_collator.py b/mojo/public/tools/manifest/manifest_collator.py
index e05763bb3ea20d0809096c4a536e4637afd1e5ef..fa95e37f21aa7d1c31c054a3925eca7f20bc5cbf 100755
--- a/mojo/public/tools/manifest/manifest_collator.py
+++ b/mojo/public/tools/manifest/manifest_collator.py
@@ -11,6 +11,7 @@ import shutil
 import sys
 import urlparse
 
+
 def ParseJSONFile(filename):
   with open(filename) as json_file:
     try:
@@ -19,18 +20,46 @@ def ParseJSONFile(filename):
       print "%s is not a valid JSON document" % filename
       return None
 
+
+def MergeDicts(left, right):
+  for k, v in right.iteritems():
+    if k not in left:
+      left[k] = v
+    else:
+      if isinstance(v, dict):
+        assert isinstance(left[k], dict)
+        MergeDicts(left[k], v)
+      elif isinstance(v, list):
+        assert isinstance(left[k], list)
+        left[k].extend(v)
+      else:
+        raise "Refusing to merge conflicting non-collection values."
+  return left
+
+
+def MergeBaseManifest(parent, base):
+  MergeDicts(parent["capabilities"], base["capabilities"])
+
+
 def main():
   parser = argparse.ArgumentParser(
       description="Collate Mojo application manifests.")
   parser.add_argument("--parent")
   parser.add_argument("--output")
   parser.add_argument("--application-name")
+  parser.add_argument("--base-manifest", default=None)
   args, children = parser.parse_known_args()
 
   parent = ParseJSONFile(args.parent)
   if parent == None:
     return 1
 
+  if args.base_manifest:
+    base = ParseJSONFile(args.base_manifest)
+    if base == None:
+      return 1
+    MergeBaseManifest(parent, base)
+
   app_path = parent['name'].split(':')[1]
   if app_path.startswith('//'):
     raise ValueError("Application name path component '%s' must not start " \