Bug 96114 [IDE] should remove dependency on IPluginRegistry
We should remove our dependency on IPluginRegistry in favour of the new IExtensionRegistry. This should be a trivial migration.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/ide/registry/CapabilityRegistry.java
/**
     * Adds the given capability to the registry. Called by
     * the CapabilityRegistryReader.
     */
    boolean addCapability(Capability capability) {
        return capabilities.add(capability);
    }
    /**
     * Adds the given capability category to the registry. Called
     * by the CapabilityRegistryReader.
     */
    boolean addCategory(Category category) {
        return categories.add(category);
    }
    /**
     * Finds the capability for the given identifier, or
     * <code>null</code> if none.
     */
    public Capability findCapability(String id) {
        Iterator itr = capabilities.iterator();
        while (itr.hasNext()) {
            Capability cap = (Capability) itr.next();
            if (id.equals(cap.getId())) {
                return cap;
            }
        }
        return null;
    }
    /**
     * Finds the category for the given identifier, or