Android: Get rid of the Camera key hack

Unnecessary now that we have a standard mechanism to disable touch input
;).

frontend/device/input.lua

@@ -570,24 +570,6 @@ function Input:handleKeyBoardEv(ev)
         return keycode
     end
 
-    -- The hardware camera button is used in Android to toggle the touchscreen
-    if keycode == "Camera" and ev.value == EVENT_VALUE_KEY_RELEASE
-        and G_reader_settings:isTrue("camera_key_toggles_touchscreen") then
-        local isAndroid, android = pcall(require, "android")
-        if isAndroid then
-            -- toggle touchscreen behaviour
-            android.toggleTouchscreenIgnored()
-
-            -- show a toast with the new behaviour
-            if android.isTouchscreenIgnored() then
-                android.notification(_("Touchscreen disabled"))
-            else
-                android.notification(_("Touchscreen enabled"))
-            end
-        end
-        return
-    end
-
     if keycode == "Power" then
         -- Kobo generates Power keycode only, we need to decide whether it's
         -- power-on or power-off ourselves.

frontend/ui/elements/common_settings_menu_table.lua

@@ -310,13 +310,6 @@ if Device:isAndroid() then
         end,
     }
 
-    -- camera key events
-    common_settings.android_camera_key = {
-        text = _("Camera key toggles touchscreen support"),
-        checked_func = function() return G_reader_settings:isTrue("camera_key_toggles_touchscreen") end,
-        callback = function() G_reader_settings:flipNilOrFalse("camera_key_toggles_touchscreen") end,
-    }
-
     common_settings.android_back_button = {
         text = _("Ignore back button completely"),
         checked_func = function() return android.isBackButtonIgnored() end,

frontend/ui/elements/filemanager_menu_order.lua

@@ -67,7 +67,6 @@ local order = {
         "backspace_as_back",
         "----------------------------",
         "android_volume_keys",
-        "android_camera_key",
         "android_haptic_feedback",
         "android_back_button",
         "----------------------------",

frontend/ui/elements/reader_menu_order.lua

@@ -111,7 +111,6 @@ local order = {
         "----------------------------",
         "page_turns_non_touch",
         "android_volume_keys",
-        "android_camera_key",
         "android_haptic_feedback",
         "android_back_button",
         "----------------------------",