Fix MockFileSystem.walk and add test.

third_party/WebKit/LayoutTests/W3CImportExpectations

 # This file controls which subdirectories of the w3c test repos we do (or don't) import.
 #
 # This file acts as a blacklist; directories and files not listed here will automatically
 # be found and imported. The only exception is that the manual tests (i.e. those with a
 # filename ending with "-manual.html" or "-manual.htm") are never imported.
 
 # When removing blacklist entries:
 # * Comment out the line rather than deleting it, to show it is intentional
 # * Change [ Skip ] to [ Pass ]
 # * Add a leading comment: ## Owners: user@example.com
@@ skipping 294 matching lines @@
 imported/wpt/webgl [ Skip ]
 imported/wpt/webmessaging [ Skip ]
 ## Owners: hta@chromium.org
 # imported/wpt/webrtc [ Pass ]
 imported/wpt/websockets [ Skip ]
 ## Owners: michaeln@chromium.org,jsbell@chromium.org
 # imported/wpt/webstorage [ Pass ]
 imported/wpt/webvtt [ Skip ]
 imported/wpt/workers [ Skip ]
 
+## Owners: raikiri@google.com
 # Skip OWNERS files in web-platform-tests. crbug.com/584660
-imported/wpt/user-timing/OWNERS [ Skip ]
-imported/wpt/common/OWNERS [ Skip ]
-imported/wpt/custom-elements/OWNERS [ Skip ]
-imported/wpt/gamepad/OWNERS [ Skip ]
-imported/wpt/FileAPI/OWNERS [ Skip ]
-imported/wpt/html/OWNERS [ Skip ]
-imported/wpt/images/OWNERS [ Skip ]
-imported/wpt/webrtc/OWNERS [ Skip ]
-imported/wpt/html-imports/OWNERS [ Skip ]
-imported/wpt/IndexedDB/OWNERS [ Skip ]
-imported/wpt/dom/OWNERS [ Skip ]
-imported/wpt/shadow-dom/OWNERS [ Skip ]
-imported/wpt/encoding/OWNERS [ Skip ]
-imported/wpt/hr-time/OWNERS [ Skip ]
-imported/wpt/pointerevents/OWNERS [ Skip ]
-imported/wpt/webstorage/OWNERS [ Skip ]
-imported/wpt/mediacapture-streams/OWNERS [ Skip ]
-imported/wpt/media/OWNERS [ Skip ]
-imported/wpt/touch-events/OWNERS [ Skip ]
-imported/wpt/uievents/OWNERS [ Skip ]
-imported/wpt/web-animations/OWNERS [ Skip ]
-imported/wpt/quirks-mode/OWNERS [ Skip ]
+#imported/wpt/user-timing/OWNERS [ Pass ]
+#imported/wpt/common/OWNERS [ Pass ]
+#imported/wpt/custom-elements/OWNERS [ Pass ]
+#imported/wpt/gamepad/OWNERS [ Pass ]
+#imported/wpt/FileAPI/OWNERS [ Pass ]
+#imported/wpt/html/OWNERS [ Pass ]
+#imported/wpt/images/OWNERS [ Pass ]
+#imported/wpt/webrtc/OWNERS [ Pass ]
+#imported/wpt/html-imports/OWNERS [ Pass ]
+#imported/wpt/IndexedDB/OWNERS [ Pass ]
+#imported/wpt/dom/OWNERS [ Pass ]
+#imported/wpt/shadow-dom/OWNERS [ Pass ]
+#imported/wpt/encoding/OWNERS [ Pass ]
+#imported/wpt/hr-time/OWNERS [ Pass ]
+#imported/wpt/pointerevents/OWNERS [ Pass ]
+#imported/wpt/webstorage/OWNERS [ Pass ]
+#imported/wpt/mediacapture-streams/OWNERS [ Pass ]
+#imported/wpt/media/OWNERS [ Pass ]
+#imported/wpt/touch-events/OWNERS [ Pass ]
+#imported/wpt/uievents/OWNERS [ Pass ]
+#imported/wpt/web-animations/OWNERS [ Pass ]
+#imported/wpt/quirks-mode/OWNERS [ Pass ]

[qyearsley, 2016/06/02 14:24:38]

This whole section can just be deleted from the file.

The reason why some lines have been commented out and have an "Owner" comment
listed above is to indicate who is responsible for which tests that are
imported.

 
 # Exceptions for individual files that fail due to bugs in the
 # upstream tests that we shouldn't bother importing until they are
 # fixed. Please include an explanation, ideally with a crbug reference
 # (if it's a blink/test tooling issue) or an upstream bug reference
 # (if the test itself is buggy).
 
 # crbug.com/490694: Needs to support *.headers.
 imported/wpt/html/dom/documents/resource-metadata-management/document-lastModified.html [ Skip ]
 imported/wpt/html/syntax/parsing-html-fragments/the-input-byte-stream-001.html [ Skip ]
@@ skipping 443 matching lines @@
 # crbug.com/574461: update-w3c-deps imports .py file with x-bit cleared
 imported/wpt/dom/nodes/Document-createElement-namespace-tests/generate.py [ Skip ]
 
 # Untriaged: Test results contain local file paths
 imported/wpt/html/semantics/document-metadata/the-base-element/base_about_blank.html [ Skip ]
 imported/wpt/html/semantics/document-metadata/the-base-element/base_srcdoc.html [ Skip ]
 
 # Untriaged: Tests don't complete.
 imported/wpt/html/semantics/document-metadata/the-style-element/style-error-01.html [ Skip ]
 imported/wpt/html/semantics/embedded-content/the-iframe-element/iframe-allowfullscreen.html [ Skip ]