Add implementation for itemprop and itemtype

Created test file

Added the stub methods for itemprop and itemscope

Resolved html5ever dependency, added ItemScope and ItemProp attr

Resolving dependency

Added pref override on metadata attributes

Resetting to original state due to change in requirement

Reverted adding attributes

1. add a customized implementation of parse_plain_attribute
2. add the following methods to HTMLElement.webidl

added itemprop and itemtype, enabled pref in test

Added initial implementation for getting itemprop property values

Adding the wireframe for testing

Implemented function to handle itemType

Corrected typo

Fixed typo bug in code

Handling duplicates for itemtype attribute values

Added the test suite structure

Added test for extra space

Added test for regular test values

Added test cases for Single property values

Test cases to check absence of itemtype and itemprop attributes

Added code to handle absence of itemtype or itemprop attributes

Added shell script to run all test cases

cleared up Cargo file

Tidying up

Removed the local test file

Removed new line for test-tidy

Ordered key in prefs.json

Fixes for test-tidy

Enabled test preferences

Created test using wpt

Creating WPT Tests for Regular and Single Prop Types

Fixed the Regular type test

Fixed tests

Removed old test case metadata

Incorporate review changes from PR

Updated MANIFEST to sync test cases

Making changed suggested in review

Removed editor folding

Removed unnecessary code

Resolving cargo conflicts

Updated PropertyNames and itemtypes implementation

Trying different data in test case

Updated manifest

Updated code based on reviews

resources/prefs.json

@@ -6,6 +6,7 @@
   "dom.customelements.enabled": true,
   "dom.forcetouch.enabled": false,
   "dom.gamepad.enabled": false,
+  "dom.microdata.testing.enabled": true,
   "dom.mouseevent.which.enabled": false,
   "dom.mozbrowser.enabled": false,
   "dom.mutation_observer.enabled": false,