patchreview: don't show Review Patch in Untitled document
The Review Patch context menu item appears in the context menu of any
KTextEditor
view, provided the patchreview plugin is loaded (the plugin
can be loaded e.g. by triggering Code=>Commit Current Project..., then
clicking the Cancel Review button). Triggering the Review Patch action
in the context menu of an Untitled (new unsaved) document causes an
assertion failure in DocumentControllerPrivate::openDocumentInternal()
:
Q_ASSERT(!inputUrl.isRelative());