ActionView::MissingTemplate

[zr2d2]

After upgrading to Rails 3.2, my app gives a missing template error

Missing partial /layouts/header with {:locale=>[:en], :formats=>[:html], :handlers=>[:erb, :builder]}. Searched in:
  * "/Users/zach/development/waterfall2/themes/demo/views"
  * "/Users/zach/development/waterfall2/app/views"
  * "/Users/zach/.rvm/gems/ruby-1.9.3-p448@waterfall/gems/gmaps4rails-1.5.6/app/views"
  * "/Users/zach/.rvm/gems/ruby-1.9.3-p448@waterfall/gems/devise-1.5.4/app/views"

when i move partials from themes/demo/views/layouts/ to app/views/layouts/ (both paths that it is searching in), the partials load and the page renders correctly. What might cause such an error?