Flamenco: Added a hidden "Submit & Quit" button.

This button can be enabled in the add-on preferences and and then be
available on the Flamenco Render panel. Pressing the button will
silently close Blender after the job has been submitted to Flamenco (for
example to click, walk away, and free up memory for when the same
machine is part of the render farm).

blender_cloud/flamenco/__init__.py

@@ -118,6 +118,19 @@ def manager_updated(self: 'FlamencoManagerGroup', context):
                                             pppm)
 
 
+def silently_quit_blender():
+    """Quit Blender without any confirmation popup."""
+
+    try:
+        prefs = bpy.context.preferences
+    except AttributeError:
+        # Backward compatibility with Blender < 2.80
+        prefs = bpy.context.user_preferences
+
+    prefs.view.use_quit_dialog = False
+    bpy.ops.wm.quit_blender()
+
+
 class FlamencoManagerGroup(PropertyGroup):
     manager = EnumProperty(
         items=available_managers,
@@ -222,6 +235,8 @@ class FLAMENCO_OT_render(async_loop.AsyncModalOperatorMixin,
     stop_upon_exception = True
     log = logging.getLogger('%s.FLAMENCO_OT_render' % __name__)
 
+    quit_after_submit = BoolProperty()
+
     async def async_execute(self, context):
         # Refuse to start if the file hasn't been saved. It's okay if
         # it's dirty, but we do need a filename and a location.
@@ -395,6 +410,9 @@ class FLAMENCO_OT_render(async_loop.AsyncModalOperatorMixin,
         else:
             self.report({'INFO'}, 'Flamenco job created.')
 
+        if self.quit_after_submit:
+            silently_quit_blender()
+
         self.quit()
 
     def validate_job_settings(self, context, settings: dict) -> bool:
@@ -955,9 +973,17 @@ class FLAMENCO_PT_render(bpy.types.Panel, FlamencoPollMixin):
         # Show current status of Flamenco.
         flamenco_status = context.window_manager.flamenco_status
         if flamenco_status in {'IDLE', 'ABORTED', 'DONE'}:
-            layout.operator(FLAMENCO_OT_render.bl_idname,
-                            text='Render on Flamenco',
-                            icon='RENDER_ANIMATION')
+            if prefs.flamenco_show_quit_after_submit_button:
+                ui = paths_layout.split(**blender.factor(0.75), align=True)
+            else:
+                ui = layout
+            ui.operator(FLAMENCO_OT_render.bl_idname,
+                        text='Render on Flamenco',
+                        icon='RENDER_ANIMATION').quit_after_submit = False
+            if prefs.flamenco_show_quit_after_submit_button:
+                ui.operator(FLAMENCO_OT_render.bl_idname,
+                            text='Submit & Quit',
+                            icon='RENDER_ANIMATION').quit_after_submit = True
             if bpy.app.debug:
                 layout.operator(FLAMENCO_OT_copy_files.bl_idname)
         elif flamenco_status == 'INVESTIGATING':