revert 9ab005a changes to UIManager:sendEvent

which would make readerui handle swipe event twice.

And use broadcastEvent to emit `FlushSettings` event.

This should fix #2225 and fix #2226.

frontend/device/generic/device.lua

@@ -90,7 +90,7 @@ function Device:intoScreenSaver()
             os.execute("killall -cont awesome")
         end
     end
-    UIManager:sendEvent(Event:new("FlushSettings"))
+    UIManager:broadcastEvent(Event:new("FlushSettings"))
 end
 
 -- ONLY used for Kindle devices
@@ -121,7 +121,7 @@ function Device:onPowerEvent(ev)
         local UIManager = require("ui/uimanager")
         -- flushing settings first in case the screensaver takes too long time
         -- that flushing has no chance to run
-        UIManager:sendEvent(Event:new("FlushSettings"))
+        UIManager:broadcastEvent(Event:new("FlushSettings"))
         DEBUG("Suspending...")
         -- always suspend in portrait mode
         self.orig_rotation_mode = self.screen:getRotationMode()

frontend/ui/uimanager.lua

@@ -402,7 +402,7 @@ function UIManager:sendEvent(event)
         end
     end
 
-    -- if the event is not consumed, widgets (from top to bottom) can
+    -- if the event is not consumed, active widgets (from top to bottom) can
     -- access it. NOTE: _window_stack can shrink on close event
     local checked_widgets = {top_widget}
     for i = #self._window_stack, 1, -1 do
@@ -416,11 +416,13 @@ function UIManager:sendEvent(event)
                     if active_widget:handleEvent(event) then return end
                 end
             end
-            -- ordinary widgets will handle this event
-            -- Note: is_always_active widgets currently are vitualkeyboard and
-            -- readerconfig
-            checked_widgets[widget] = true
-            if widget.widget:handleEvent(event) then return end
+            if widget.widget.is_always_active then
+                -- active widgets will handle this event
+                -- Note: is_always_active widgets currently are vitualkeyboard and
+                -- readerconfig
+                checked_widgets[widget] = true
+                if widget.widget:handleEvent(event) then return end
+            end
         end
     end
 end