Revert 2c7bebb5f2c873850c2b2d82013cab4eb3d4913c
Revert 2c7bebb5f2c873850c2b2d82013cab4eb3d4913c

On reflection, this seems too dangerous:

   - Somebody excluded flash for a reason, and without knowing that
     reason, it seems dangerous.

   - Imagine a flash game with key bindings.  Perhaps it uses ? to
     show the key bindings, and ESC to hide them again.  With
     2c7bebb5f2c873850c2b2d82013cab4eb3d4913c, you can never hide the
     key bindings (I think).

All in all, this just seems too risky.

mrmr1993/vimium,hhsue/vimium,cyrixhero/vimium,decaffeinate-examples/vimium,hhsue/vimium,borgified/vimium,dimatter/vimium,PrestanceDesign/vimium,mrmr1993/vimium,wildeyes/vimium,PickRelated/vimium,elegantwww/vimium,poacher2k/vimium,willsALMANJ/vimium,wildeyes/vimium,dimatter/vimium,crazypenguincode/vimium,Aleroniponi/vimium,Lw-Cui/vimium,PickRelated/vimium,PickRelated/vimium,philc/vimium,zhangmin510/vimium,douglas-larocca/vimium,justalittlenoob/vimium,decaffeinate-examples/vimium,cyrixhero/vimium,elderbas/vimium,Aleroniponi/vimium,dimatter/vimium,tuchangwei/vimium,tuchangwei/vimium,Lw-Cui/vimium,Robinson10240/vimium,smblott-github/vimium,gdh1995/vimium,poacher2k/vimium,willsALMANJ/vimium,bkudria/vimium,Robinson10240/vimium,VPashkov/vimium,smblott-github/vimium,Aleroniponi/vimium,Lw-Cui/vimium,csmalin/vimium,elderbas/vimium,philc/vimium,douglas-larocca/vimium,poacher2k/vimium,douglas-larocca/vimium,elegantwww/vimium,bkudria/vimium,hhsue/vimium,PrestanceDesign/vimium,justalittlenoob/vimium,crazypenguincode/vimium,mrmr1993/vimium,elegantwww/vimium,borgified/vimium,tuchangwei/vimium,willsALMANJ/vimium,bkudria/vimium,smblott-github/vimium,borgified/vimium,Robinson10240/vimium,csmalin/vimium,VPashkov/vimium,csmalin/vimium,gdh1995/vimium,gdh1995/vimium,wildeyes/vimium,zhangmin510/vimium,VPashkov/vimium,zhangmin510/vimium,justalittlenoob/vimium,PrestanceDesign/vimium,elderbas/vimium,philc/vimium,cyrixhero/vimium,decaffeinate-examples/vimium