Bug 126779 [IDE] Removed deprecated project capabilities API and implementation
It was created then deprecated before 2.0 shipped. As has never been API and we don't use it we should delete it.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/registry/CapabilityRegistry.java
* <code>null</code> if none.
     */
    public Category findCategory(String id) {
        Iterator itr = categories.iterator();
        while (itr.hasNext()) {
            Category cat = (Category) itr.next();
            if (id.equals(cat.getRootPath())) {
                return cat;
            }
        }
        return null;
    }
    /**
     * Finds the capability for each specified identifier.
     * Any <code>null</code> entries in the resulting array
     * are for identifiers to which no capability exist.
     */
    public Capability[] findCapabilities(String[] ids) {
        int count = capabilities.size();
        Capability[] results = new Capability[ids.length];
        for (int i = 0; i < ids.length; i++) {
            String id = ids[i];
            for (int j = 0; j < count; j++) {
                Capability cap = (Capability) capabilities.get(j);
                if (cap.getId().equals(id)) {
                    results[i] = cap;
                    break;
                }
            }
        }