[epiphany] (17 commits) Non-fast-forward update to branch mcatanzaro/#587

[Jan-Michael Brummer <jbrummer src gnome org>]

The branch 'mcatanzaro/#587' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  567499e... window: Watch for stalled web process when closing tabs
  9022350... window: Watch for stalled web process when closing window

Commits added to the branch:

  724eb5e... Revert "Enable web process sandbox" (*)
  1a00b21... flatpak: Add libhandy (*)
  ed4b901... build: Add libhandy-0.0 dependency (*)
  701b6aa... main: Init libhandy (*)
  4c2af23... Make margins around the title widget adaptive (*)
  b4dfb49... window: Make triggering the narrow mode less aggressive (*)
  4fc3fa8... prefs-dialog: Fix crash when locale is saved by older Epiph (*)
  786927e... web-view: Handle NULL URIs in ephy_web_view_set_address() (*)
  673564b... Tags with empty labels are no longer allowed in bookmarks (*)
  95ef623... Remove extra heading level from CONTRIBUTING.md (*)
  9da3703... bookmark-row: Insert left margin on the favicon of each boo (*)
  04d6bf2... bookmark-row: Use g_autoptr (*)
  3d43701... bookmark-properties-grid: Use g_auto* (*)
  b4f25f6... add-bookmark-popover: Use g_auto* (*)
  97f56c5... web-view: Show all files when running the file chooser for  (*)
  e14780a... window: Watch for stalled web process when closing tabs
  4efc834... window: Watch for stalled web process when closing window

(*) This commit already existed in another branch; no separate mail sent