Allow [Pref] annotations on worker-exposed interfaces.

Servo does not have the same main-thread limitation as Gecko here.

components/script/dom/bindings/codegen/parser/WebIDL.py

@@ -1239,12 +1239,6 @@ class IDLInterface(IDLObjectWithScope, IDLExposureMixins):
                                               alias,
                                               [member.location, m.location])
 
-        if (self.getExtendedAttribute("Pref") and
-            self._exposureGlobalNames != set([self.parentScope.primaryGlobalName])):
-            raise WebIDLError("[Pref] used on an interface that is not %s-only" %
-                              self.parentScope.primaryGlobalName,
-                              [self.location])
-
         for attribute in ["CheckAnyPermissions", "CheckAllPermissions"]:
             if (self.getExtendedAttribute(attribute) and
                 self._exposureGlobalNames != set([self.parentScope.primaryGlobalName])):
@@ -3459,12 +3453,6 @@ class IDLInterfaceMember(IDLObjectWithIdentifier, IDLExposureMixins):
         IDLExposureMixins.finish(self, scope)
 
     def validate(self):
-        if (self.getExtendedAttribute("Pref") and
-            self.exposureSet != set([self._globalScope.primaryGlobalName])):
-            raise WebIDLError("[Pref] used on an interface member that is not "
-                              "%s-only" % self._globalScope.primaryGlobalName,
-                              [self.location])
-
         for attribute in ["CheckAnyPermissions", "CheckAllPermissions"]:
             if (self.getExtendedAttribute(attribute) and
                 self.exposureSet != set([self._globalScope.primaryGlobalName])):

components/script/dom/bindings/codegen/parser/pref-main-thread.patch

@@ -0,0 +1,28 @@
+--- WebIDL.py
++++ WebIDL.py
+@@ -1239,12 +1239,6 @@ class IDLInterface(IDLObjectWithScope, IDLExposureMixins):
+                                               alias,
+                                               [member.location, m.location])
+ 
+-        if (self.getExtendedAttribute("Pref") and
+-            self._exposureGlobalNames != set([self.parentScope.primaryGlobalName])):
+-            raise WebIDLError("[Pref] used on an interface that is not %s-only" %
+-                              self.parentScope.primaryGlobalName,
+-                              [self.location])
+-
+         for attribute in ["CheckAnyPermissions", "CheckAllPermissions"]:
+             if (self.getExtendedAttribute(attribute) and
+                 self._exposureGlobalNames != set([self.parentScope.primaryGlobalName])):
+@@ -3459,12 +3453,6 @@ class IDLInterfaceMember(IDLObjectWithIdentifier, IDLExposureMixins):
+         IDLExposureMixins.finish(self, scope)
+ 
+     def validate(self):
+-        if (self.getExtendedAttribute("Pref") and
+-            self.exposureSet != set([self._globalScope.primaryGlobalName])):
+-            raise WebIDLError("[Pref] used on an interface member that is not "
+-                              "%s-only" % self._globalScope.primaryGlobalName,
+-                              [self.location])
+-
+         for attribute in ["CheckAnyPermissions", "CheckAllPermissions"]:
+             if (self.getExtendedAttribute(attribute) and
+                 self.exposureSet != set([self._globalScope.primaryGlobalName])):

components/script/dom/bindings/codegen/parser/update.sh

@@ -1,6 +1,7 @@
 wget https://mxr.mozilla.org/mozilla-central/source/dom/bindings/parser/WebIDL.py?raw=1 -O WebIDL.py
 patch < abstract.patch
 patch < debug.patch
+patch < pref-main-thread.patch
 
 wget https://hg.mozilla.org/mozilla-central/archive/tip.tar.gz/dom/bindings/parser/tests/ -O tests.tar.gz
 rm -r tests