Fixed a test.

* tests/install-basic.el: Use new function names.
Bugfix for doc-view support.

* lisp/pdf-info.el (pdf-info--normalize-file-or-buffer): Check for
  renamed variable doc-view--buffer-file-name.
Documentation fix.

* lisp/pdf-info.el (pdf-info-restart-process-p): Fix documentation.
  (pdf-info-asynchronous): Documented variable.
  (pdf-info-interrupt): Documented function.
Tiny fix.

* lisp/pdf-annot.el (pdf-annot-list-operation-function): Remove
  unsupported complete operation.
Don't try to clear the cache if therer is none.

* lisp/pdf-cache.el (pdf-cache-clear-data-of-pages,
  pdf-cache-clear-data): Check if buffer has a data cache.
Map correct function name.

* lisp/pdf-view.el (pdf-view-mode-map): Mode is called pdf-dark-minor-mode.
Documentation typo fix.
Added TODO item.
Detailed TODO item.