diff --git a/components/style/keyframes.rs b/components/style/keyframes.rs
index c12856dd108..cc8a9229b85 100644
--- a/components/style/keyframes.rs
+++ b/components/style/keyframes.rs
@@ -405,7 +405,7 @@ impl<'a, 'b> DeclarationParser for KeyframeDeclarationParser<'a, 'b> {
 
     fn parse_value(&mut self, name: &str, input: &mut Parser) -> Result<ParsedDeclaration, ()> {
         let id = try!(PropertyId::parse(name.into()));
-        match ParsedDeclaration::parse(id, self.context, input, true) {
+        match ParsedDeclaration::parse(id, self.context, input) {
             Ok(parsed) => {
                 // In case there is still unparsed text in the declaration, we should roll back.
                 if !input.is_exhausted() {
diff --git a/components/style/properties/declaration_block.rs b/components/style/properties/declaration_block.rs
index bd23f73748f..fd0704b8971 100644
--- a/components/style/properties/declaration_block.rs
+++ b/components/style/properties/declaration_block.rs
@@ -628,7 +628,7 @@ pub fn parse_one_declaration(id: PropertyId,
                              -> Result<ParsedDeclaration, ()> {
     let context = ParserContext::new(Origin::Author, url_data, error_reporter, Some(CssRuleType::Style));
     Parser::new(input).parse_entirely(|parser| {
-        ParsedDeclaration::parse(id, &context, parser, false)
+        ParsedDeclaration::parse(id, &context, parser)
             .map_err(|_| ())
     })
 }
@@ -653,7 +653,7 @@ impl<'a, 'b> DeclarationParser for PropertyDeclarationParser<'a, 'b> {
                    -> Result<(ParsedDeclaration, Importance), ()> {
         let id = try!(PropertyId::parse(name.into()));
         let parsed = input.parse_until_before(Delimiter::Bang, |input| {
-            ParsedDeclaration::parse(id, self.context, input, false)
+            ParsedDeclaration::parse(id, self.context, input)
                 .map_err(|_| ())
         })?;
         let importance = match input.try(parse_important) {
diff --git a/components/style/properties/properties.mako.rs b/components/style/properties/properties.mako.rs
index db9eaa9651f..d4957461fc2 100644
--- a/components/style/properties/properties.mako.rs
+++ b/components/style/properties/properties.mako.rs
@@ -976,8 +976,7 @@ impl ParsedDeclaration {
     /// This will not actually parse Importance values, and will always set things
     /// to Importance::Normal. Parsing Importance values is the job of PropertyDeclarationParser,
     /// we only set them here so that we don't have to reallocate
-    pub fn parse(id: PropertyId, context: &ParserContext, input: &mut Parser,
-                 in_keyframe_block: bool)
+    pub fn parse(id: PropertyId, context: &ParserContext, input: &mut Parser)
                  -> Result<ParsedDeclaration, PropertyDeclarationParseError> {
         let rule_type = context.rule_type();
         debug_assert!(rule_type == CssRuleType::Keyframe ||
@@ -1000,7 +999,7 @@ impl ParsedDeclaration {
                 LonghandId::${property.camel_case} => {
                     % if not property.derived_from:
                         % if not property.allowed_in_keyframe_block:
-                            if in_keyframe_block {
+                            if rule_type == CssRuleType::Keyframe {
                                 return Err(PropertyDeclarationParseError::AnimationPropertyInKeyframeBlock)
                             }
                         % endif
@@ -1033,7 +1032,7 @@ impl ParsedDeclaration {
             % for shorthand in data.shorthands:
                 ShorthandId::${shorthand.camel_case} => {
                     % if not shorthand.allowed_in_keyframe_block:
-                        if in_keyframe_block {
+                        if rule_type == CssRuleType::Keyframe {
                             return Err(PropertyDeclarationParseError::AnimationPropertyInKeyframeBlock)
                         }
                     % endif
diff --git a/components/style/supports.rs b/components/style/supports.rs
index 37926c2fc9e..932b8bc2880 100644
--- a/components/style/supports.rs
+++ b/components/style/supports.rs
@@ -213,7 +213,7 @@ impl Declaration {
         };
         let mut input = Parser::new(&self.val);
         let context = ParserContext::new_with_rule_type(cx, Some(CssRuleType::Style));
-        let res = ParsedDeclaration::parse(id, &context, &mut input, /* in_keyframe */ false);
+        let res = ParsedDeclaration::parse(id, &context, &mut input);
         let _ = input.try(parse_important);
         res.is_ok() && input.is_exhausted()
     }
diff --git a/ports/geckolib/glue.rs b/ports/geckolib/glue.rs
index 438bd79369d..f4867e2b292 100644
--- a/ports/geckolib/glue.rs
+++ b/ports/geckolib/glue.rs
@@ -952,7 +952,7 @@ pub extern "C" fn Servo_ParseProperty(property: *const nsACString, value: *const
     let reporter = StdoutErrorReporter;
     let context = ParserContext::new(Origin::Author, url_data, &reporter, Some(CssRuleType::Style));
 
-    match ParsedDeclaration::parse(id, &context, &mut Parser::new(value), false) {
+    match ParsedDeclaration::parse(id, &context, &mut Parser::new(value)) {
         Ok(parsed) => {
             let global_style_data = &*GLOBAL_STYLE_DATA;
             let mut block = PropertyDeclarationBlock::new();