fix a crash when removing the annotation added from mac

about 10%.Removing call of dictLookup in invalidateAppearance to avoid
the crash,and this code is not necessary.This may be the same bug as
issues #278.
11 jobs for master in 20 minutes and 20 seconds (queued for 3 seconds)
latest
Status Job ID Name Coverage
  Build
passed #4523361
build

00:04:41

passed #4523366
build_android

00:00:47

passed #4523362
build_clang_libcpp

00:02:44

passed #4523365
build_clazy

00:14:13

passed #4523364
build_mingw64_fedora

00:03:02

passed #4523363
build_ubuntu_16_04

00:02:14

passed #4523360
clang_format

00:00:47

 
  Document
passed #4523368
cpp_docs

00:05:16

passed #4523369
glib_docs

00:05:38

passed #4523367
qt5_docs

00:03:02

 
  Publish
passed #4523370
trigger_pages

00:00:23