Fix some links in documentation related to layout tests.

docs/testing/layout_test_expectations.md

 # Layout Test Expectations and Baselines
 
 
 The primary function of the LayoutTests is as a regression test suite; this
 means that, while we care about whether a page is being rendered correctly, we
 care more about whether the page is being rendered the way we expect it to. In
 other words, we look more for changes in behavior than we do for correctness.
 
 [TOC]
 
@@ skipping 145 matching lines @@
   longer than the usual timeout to run. Slow tests are given 5x the usual
   timeout.
 * [SmokeTests](../../third_party/WebKit/LayoutTests/SmokeTests): A small subset
   of tests that we run on the Android bot.
 * [StaleTestExpectations](../../third_party/WebKit/LayoutTests/StaleTestExpectations):
   Platform-specific lines that have been in TestExpectations for many months.
   They're moved here to get them out of the way of people doing rebaselines
   since they're clearly not getting fixed anytime soon.
 * [W3CImportExpectations](../../third_party/WebKit/LayoutTests/W3CImportExpectations):
   A record of which W3C tests should be imported or skipped.
-* [WPTServeExpectations](../../third_party/WebKit/LayoutTests/WPTServeExpectations):
-  Expectations for tests that fail differently when run under the W3C's wptserve
-  HTTP server with the `--enable-wptserve flag`. This is an experimental feature
-  at this time.
-
 
 ### Flag-specific expectations files
 
 It is possible to handle tests that only fail when run with a particular flag
 being passed to `content_shell`. See
 [LayoutTests/FlagExpectations/README.txt](../../third_party/WebKit/LayoutTests/FlagExpectations/README.txt)
 for more.
 
 ## Updating the expectations files
 
@@ skipping 108 matching lines @@
 
 You can verify that any changes you've made to an expectations file are correct
 by running:
 
 ```bash
 third_party/WebKit/Tools/Scripts/lint-test-expectations
 ```
 
 which will cycle through all of the possible combinations of configurations
 looking for problems.