* hash.c (rb_hash_delete): return Qnil if there are no corresponding
  entry. [Bug #10623]
* hash.c (rb_hash_delete_entry): try delete and return Qundef if there
  are no corresponding entry.
* internal.h: add rb_hash_delete_entry()'s declaration.
* symbol.c: use rb_hash_delete_entry().
* thread.c: use rb_hash_delete_entry().
* ext/-test-/hash/delete.c: use rb_hash_delete_entry().



git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48958 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
* common.mk (up): propagate verbose option.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@48959 b2dd03c8-39d4-4d8f-98ff-823fe69b080e