Add support for showing CSS with distilled articles.

components/dom_distiller/content/dom_distiller_viewer_source.cc

Index: components/dom_distiller/content/dom_distiller_viewer_source.cc
diff --git a/components/dom_distiller/content/dom_distiller_viewer_source.cc b/components/dom_distiller/content/dom_distiller_viewer_source.cc
index d83252b5433babb0b0d03d7dc377bb78dfc4a863..aa150d7604da61996bc2bf09b570f19ed27dc63a 100644
--- a/components/dom_distiller/content/dom_distiller_viewer_source.cc
+++ b/components/dom_distiller/content/dom_distiller_viewer_source.cc
@@ -26,14 +26,17 @@
 
 namespace {
 
+const char kCssPath[] = "readability.css";
+
 std::string ReplaceHtmlTemplateValues(std::string title, std::string content) {
   base::StringPiece html_template =
       ResourceBundle::GetSharedInstance().GetRawDataResource(
           IDR_DOM_DISTILLER_VIEWER_HTML);
   std::vector<std::string> substitutions;
-  substitutions.push_back(title);    // $1
-  substitutions.push_back(title);    // $2
-  substitutions.push_back(content);  // $3
+  substitutions.push_back(title);     // $1
+  substitutions.push_back(kCssPath);  // $2
+  substitutions.push_back(title);     // $3
+  substitutions.push_back(content);   // $4
   return ReplaceStringPlaceholders(html_template, substitutions, NULL);
 }
 
@@ -114,8 +117,17 @@ void DomDistillerViewerSource::StartDataRequest(
   DCHECK(render_view_host);
   CHECK_EQ(0, render_view_host->GetEnabledBindings());
 
+  if (kCssPath == path) {
+    std::string css = ResourceBundle::GetSharedInstance()
+                          .GetRawDataResource(IDR_DISTILLER_CSS)
+                          .as_string();
+    callback.Run(base::RefCountedString::TakeString(&css));
+    return;
+  }
+
   scoped_ptr<RequestViewerHandle> request_viewer_handle(
       new RequestViewerHandle(callback));
+
   std::string entry_id = StringToUpperASCII(path);
   scoped_ptr<ViewerHandle> viewer_handle =
       dom_distiller_service_->ViewEntry(request_viewer_handle.get(), entry_id);
@@ -125,7 +137,7 @@ void DomDistillerViewerSource::StartDataRequest(
     // request is not cancelled. The |RequestViewerHandle| will delete itself
     // after receiving the callback.
     request_viewer_handle.get()->TakeViewerHandle(viewer_handle.Pass());
-    (void) request_viewer_handle.release();
+    (void)request_viewer_handle.release();
   } else {
     std::string title = l10n_util::GetStringUTF8(
         IDS_DOM_DISTILLER_VIEWER_FAILED_TO_FIND_ARTICLE_TITLE);
@@ -138,6 +150,8 @@ void DomDistillerViewerSource::StartDataRequest(
 
 std::string DomDistillerViewerSource::GetMimeType(const std::string& path)
     const {
+  if (path == kCssPath)
+    return "text/css";
   return "text/html";
 }
 
@@ -149,9 +163,16 @@ bool DomDistillerViewerSource::ShouldServiceRequest(
 void DomDistillerViewerSource::WillServiceRequest(
     const net::URLRequest* request,
     std::string* path) const {
-  // Since the full request is not available to StartDataRequest, replace the
-  // path to contain the data needed.
-  *path = request->url().host();
+  if (*path != kCssPath) {
+    // Since the full request is not available to StartDataRequest, replace the
+    // path to contain the data needed.
+    *path = request->url().host();
+  }
 };
 
+std::string DomDistillerViewerSource::GetContentSecurityPolicyObjectSrc()
+    const {
+  return "object-src 'none'; style-src 'self'";
+}
+
 }  // namespace dom_distiller