[librsvg] (17 commits) ...Merge branch 'acquired-node'

[Federico Mena Quintero <federico src gnome org>]

Summary of changes:

  8055542... gitlab#227 - Catch negative values in stroke-dasharray
  818041c... gradient.rs: Release acquired nodes if they are not of the 
  f983cbc... NodeUse: release the acquired node as soon as possible; to 
  2c45ddf... AcquiredNode: new wrapper over acquire_node()/release_node(
  b7967ea... gradient.rs: Use AcquiredNode
  ae59564... marker.rs: Don't pass an extra c_node; we can get it from t
  0356f4e... marker.rs: use AcquiredNode
  ea25d8f... paint_server.rs: Use AcquiredNode
  9d4245b... structure.rs: Use AcquiredNode
  6749d57... pattern.rs: Use AcquiredNode
  bde7c3b... drawing_ctx.rs: Removed unused acquire_node()/acquire_node_
  28d3c9e... pattern.rs: Remove the FallbackSource stack
  52773b3... pattern.rs: Handle patterns with no children in a cleaner w
  fdb9379... Prettify the rather horrible while() loop in resolve_patter
  8f4b324... gradient.rs: Remove FallbackSource; use acquired nodes inst
  1340c08... gradient.rs: Refactor the resolution loop similarly to patt
  67deed8... Merge branch 'acquired-node'