Running Apache Rat (http://incubator.apache.org/rat/) against the android source tree (java -jar apache-rat-0.8.jar incubator-cordova-android) flagged still the following files, categorized by required action. I already filtered out some files (VERSION, .project, etc. for which a header is clearly not needed as discussed in LEGAL-124)
Simple bin scripts (header not absolutely needed for such small files, see LEGAL-124):
Node.js modules (no header changes, but these need to be mentioned in LICENSE or alternatively replaced with auto-downloaded npm dependencies):
Template files (not sure if a header is appropriate for such templates, see LEGAL-124)
Test scripts (header not absolutely needed for such small files, see LEGAL-124):
Framework files (need case-by-case review):
On a related note, the framework/libs/junit-4.10.jar archive mentioned in NOTICE and LICENSE is not present in the source tree, so it probably shouldn't be mentioned in those files.