Rename c.allow_styles and repurpose it for convenient overriding.

This enables fine-grained control to un-block CSS without affecting
whether it would be displayed based on user settings or context.

r2/r2/controllers/reddit_base.py

@@ -892,15 +892,16 @@ class RedditController(MinimalController):
                 return self.intermediate_redirect("/over18")
 
         #check whether to allow custom styles
-        c.allow_styles = self.allow_stylesheets
+        c.allow_styles = True
+        c.can_apply_styles = self.allow_stylesheets
         if g.css_killswitch:
-            c.allow_styles = False
+            c.can_apply_styles = False
         #if the preference is set and we're not at a cname
         elif not c.user.pref_show_stylesheets and not c.cname:
-            c.allow_styles = False
+            c.can_apply_styles = False
         #if the site has a cname, but we're not using it
         elif c.site.domain and c.site.css_on_cname and not c.cname:
-            c.allow_styles = False
+            c.can_apply_styles = False
 
     def check_modified(self, thing, action,
                        private=True, max_age=0, must_revalidate=True):

r2/r2/templates/reddit.html

@@ -67,7 +67,7 @@
     <link rel="shorturl" href="http://${thing.shortlink}"/>
   %endif
 
-  %if c.allow_styles and c.site.stylesheet_contents:
+  %if c.can_apply_styles and c.allow_styles and c.site.stylesheet_contents:
      <% inline_stylesheet = (
           len(c.site.stylesheet_contents) < 1024
           and '<' not in c.site.stylesheet_contents) %>

r2/r2/templates/redditheader.html

@@ -35,7 +35,7 @@
     <%
         header_title = c.site.header_title
         d = DefaultSR()
-        if c.site.header and c.allow_styles:
+        if c.site.header and c.can_apply_styles and c.allow_styles:
             header_img = c.site.header
             header_size = c.site.header_size
         else: