Rename ReadOnly to OptionalReadOnly.

Fixes #399.

Author: Ms2ger

index.bs

@@ -1363,7 +1363,7 @@ No [=extended attributes=] defined in this specification are applicable to [=inc
         Const
         RegularOperation
         Stringifier
-        ReadOnly AttributeRest
+        OptionalReadOnly AttributeRest
 </pre>
 
 <pre class="grammar" id="prod-IncludesStatement">
@@ -1839,9 +1839,9 @@ The following extended attributes are applicable to constants:
 An <dfn id="dfn-attribute" export>attribute</dfn> is an [=interface member=] or [=namespace member=]
 (matching
 <emu-t>inherit</emu-t> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
-<emu-t>static</emu-t> <emu-nt><a href="#prod-ReadOnly">ReadOnly</a></emu-nt> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
-<emu-t>stringifier</emu-t> <emu-nt><a href="#prod-ReadOnly">ReadOnly</a></emu-nt> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
-<emu-nt><a href="#prod-ReadOnly">ReadOnly</a></emu-nt> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
+<emu-t>static</emu-t> <emu-nt><a href="#prod-OptionalReadOnly">OptionalReadOnly</a></emu-nt> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
+<emu-t>stringifier</emu-t> <emu-nt><a href="#prod-OptionalReadOnly">OptionalReadOnly</a></emu-nt> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
+<emu-nt><a href="#prod-OptionalReadOnly">OptionalReadOnly</a></emu-nt> <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>,
 or <emu-nt><a href="#prod-AttributeRest">AttributeRest</a></emu-nt>)
 that is used to declare data fields with a given type and
 [=identifier=] whose value can
@@ -2009,8 +2009,8 @@ are applicable only to regular attributes:
         "required"
 </pre>
 
-<pre class="grammar" id="prod-ReadOnly">
-    ReadOnly :
+<pre class="grammar" id="prod-OptionalReadOnly">
+    OptionalReadOnly :
         "readonly"
         ε
 </pre>
@@ -2911,7 +2911,7 @@ a [=static attribute=].
 
 <pre class="grammar" id="prod-StringifierRest">
     StringifierRest :
-        ReadOnly AttributeRest
+        OptionalReadOnly AttributeRest
         RegularOperation
         ";"
 </pre>
@@ -3255,7 +3255,7 @@ to an instance of the interface.
 
 <pre class="grammar" id="prod-StaticMemberRest">
     StaticMemberRest :
-        ReadOnly AttributeRest
+        OptionalReadOnly AttributeRest
         RegularOperation
 </pre>