Make dummyURL from the basic URL parser with a special scheme

Per discussion in #252, this creates a dummy URL from the basic URL parser rather than using URL records directly to canonicalize components.

Also this specifies a special scheme as a default scheme.

Author: sisidovski

spec.bs

@@ -599,6 +599,13 @@ A <dfn>component</dfn> is a [=struct=] with the following [=struct/items=]:
   1. Return |result|.
 </div>
 
+<div algorithm>
+  To <dfn export for="URL pattern">create a dummy URL</dfn>:
+
+  1. Let |dummyInput| be "`https://dummy.invalid/`".
+  1. Return the result of running the [=basic URL parser=] on |dummyInput|.
+</div>
+
 The <dfn>default options</dfn> is an [=options=] [=struct=] with [=options/delimiter code point=] set to the empty string and [=options/prefix code point=] set to the empty string.
 
 The <dfn>hostname options</dfn> is an [=options=] [=struct=] with [=options/delimiter code point=] set "`.`" and [=options/prefix code point=] set to the empty string.
@@ -1704,18 +1711,17 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize a protocol</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
-  1. Let |parseResult| be the result of running the [=basic URL parser=] given |value| followed by "`://dummy.test`", with |dummyURL| as <i>[=basic URL parser/url=]</i>.
+  1. Let |parseResult| be the result of running the [=basic URL parser=] given |value| followed by "`://dummy.invalid/`".
      <p class="note">Note, [=basic URL parser/state override=] is not used here because it enforces restrictions that are only appropriate for the {{URL/protocol}} setter.  Instead we use the protocol to parse a dummy URL using the normal parsing entry point.</p>
   1. If |parseResult| is failure, then throw a {{TypeError}}.
-  1. Return |dummyURL|'s [=url/scheme=].
+  1. Return |parseResult|'s [=url/scheme=].
 </div>
 
 <div algorithm>
   To <dfn>canonicalize a username</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. [=Set the username=] given |dummyURL| and |value|.
   1. Return |dummyURL|'s [=url/username=].
 </div>
@@ -1724,7 +1730,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize a password</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. [=Set the password=] given |dummyURL| and |value|.
   1. Return |dummyURL|'s [=url/password=].
 </div>
@@ -1733,7 +1739,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize a hostname</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. Let |parseResult| be the result of running the [=basic URL parser=] given |value| with |dummyURL| as <i>[=basic URL parser/url=]</i> and [=hostname state=] as <i>[=basic URL parser/state override=]</i>.
   1. If |parseResult| is failure, then throw a {{TypeError}}.
   1. Return |dummyURL|'s [=url/host=], [=host serializer|serialized=], or empty string if it is null.
@@ -1760,7 +1766,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize a port</dfn> given a string |portValue| and optionally a string |protocolValue|:
 
   1. If |portValue| is the empty string, return |portValue|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. If |protocolValue| was given, then set |dummyURL|'s [=url/scheme=] to |protocolValue|.
      <p class="note">Note, we set the [=URL record=]'s [=url/scheme=] in order for the [=basic URL parser=] to recognize and normalize default port values.</p>
   1. Let |parseResult| be the result of running [=basic URL parser=] given |portValue| with |dummyURL| as <i>[=basic URL parser/url=]</i> and [=port state=] as <i>[=basic URL parser/state override=]</i>.
@@ -1779,7 +1785,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
       <p>Note, implementations are free to simply disable slash prepending in their URL parsing code instead of paying the performance penalty of inserting and removing characters in this algorithm.
     </div>
   1. Append |value| to the end of |modified value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. Run [=basic URL parser=] given |modified value| with |dummyURL| as <i>[=basic URL parser/url=]</i> and [=path start state=] as <i>[=basic URL parser/state override=]</i>.
   1. Let |result| be the result of [=URL path serializing=] |dummyURL|.
   1. If |leading slash| is false, then set |result| to the [=code point substring to the end of the string|code point substring=] from 2 to the end of the string within |result|.
@@ -1790,7 +1796,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize an opaque pathname</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. Set |dummyURL|'s [=url/path=] to the empty string.
   1. Let |parseResult| be the result of running [=basic URL parser|URL parsing=] given |value| with |dummyURL| as <i>[=basic URL parser/url=]</i> and [=basic URL parser/opaque path state=] as <i>[=basic URL parser/state override=]</i>.
   1. If |parseResult| is failure, then throw a {{TypeError}}.
@@ -1801,7 +1807,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize a search</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. Set |dummyURL|'s [=url/query=] to the empty string.
   1. Run [=basic URL parser=] given |value| with |dummyURL| as <i>[=basic URL parser/url=]</i> and [=query state=] as <i>[=basic URL parser/state override=]</i>.
   1. Return |dummyURL|'s [=url/query=].
@@ -1811,7 +1817,7 @@ To <dfn>convert a modifier to a string</dfn> given a [=part/modifier=] |modifier
   To <dfn>canonicalize a hash</dfn> given a string |value|:
 
   1. If |value| is the empty string, return |value|.
-  1. Let |dummyURL| be a new [=URL record=].
+  1. Let |dummyURL| be the result of [=creating a dummy URL=].
   1. Set |dummyURL|'s [=url/fragment=] to the empty string.
   1. Run [=basic URL parser=] given |value| with |dummyURL| as <i>[=basic URL parser/url=]</i> and [=fragment state=] as <i>[=basic URL parser/state override=]</i>.
   1. Return |dummyURL|'s [=url/fragment=].