[NotLanded] Implement the fetching algorithm of the Web Manifest.

Source/core/fetch/ResourceFetcher.cpp

Index: Source/core/fetch/ResourceFetcher.cpp
diff --git a/Source/core/fetch/ResourceFetcher.cpp b/Source/core/fetch/ResourceFetcher.cpp
index 2c18ad2f1539d303d74975e2e1d590c71a9e4eec..2baf25239a4212a4f1cde0d3551085d916be567f 100644
--- a/Source/core/fetch/ResourceFetcher.cpp
+++ b/Source/core/fetch/ResourceFetcher.cpp
@@ -96,15 +96,14 @@ static Resource* createResource(Resource::Type type, const ResourceRequest& requ
     case Resource::Raw:
     case Resource::TextTrack:
     case Resource::Media:
+    case Resource::ImportResource:
         return new RawResource(request, type);
     case Resource::XSLStyleSheet:
         return new XSLStyleSheetResource(request, charset);
     case Resource::LinkPrefetch:
-        return new Resource(request, Resource::LinkPrefetch);
     case Resource::LinkSubresource:
-        return new Resource(request, Resource::LinkSubresource);
-    case Resource::ImportResource:
-        return new RawResource(request, type);
+    case Resource::Manifest:
+        return new Resource(request, type);
     }
 
     ASSERT_NOT_REACHED();
@@ -126,6 +125,7 @@ static ResourceLoadPriority loadPriority(Resource::Type type, const FetchRequest
     case Resource::Script:
     case Resource::Font:
     case Resource::ImportResource:
+    case Resource::Manifest:
         return ResourceLoadPriorityMedium;
     case Resource::Image:
         // We'll default images to VeryLow, and promote whatever is visible. This improves
@@ -218,6 +218,8 @@ static WebURLRequest::RequestContext requestContextFromType(const ResourceFetche
         return WebURLRequest::RequestContextPrefetch;
     case Resource::LinkSubresource:
         return WebURLRequest::RequestContextSubresource;
+    case Resource::Manifest:
+        return WebURLRequest::RequestContextManifest;
     case Resource::TextTrack:
         return WebURLRequest::RequestContextTrack;
     case Resource::SVGDocument:
@@ -413,6 +415,13 @@ ResourcePtr<RawResource> ResourceFetcher::fetchTextTrack(FetchRequest& request)
     return toRawResource(requestResource(Resource::TextTrack, request));
 }
 
+ResourcePtr<Resource> ResourceFetcher::fetchManifest(FetchRequest& request)
+{
+    ASSERT(request.resourceRequest().frameType() == WebURLRequest::FrameTypeNone);
+    request.mutableResourceRequest().setRequestContext(WebURLRequest::RequestContextManifest);
+    return requestResource(Resource::Manifest, request);
+}
+
 void ResourceFetcher::preCacheSubstituteDataForMainResource(const FetchRequest& request, const SubstituteData& substituteData)
 {
     const KURL& url = request.url();
@@ -435,6 +444,8 @@ bool ResourceFetcher::checkInsecureContent(Resource::Type type, const KURL& url,
 {
     if (treatment == TreatAsDefaultForType) {
         switch (type) {
+        // Blockable content list is defined here:
+        // http://w3c.github.io/webappsec/specs/mixedcontent/#category-blockable
         case Resource::XSLStyleSheet:
             ASSERT(RuntimeEnabledFeatures::xsltEnabled());
         case Resource::Script:
@@ -447,6 +458,7 @@ bool ResourceFetcher::checkInsecureContent(Resource::Type type, const KURL& url,
             break;
 
         case Resource::Font:
+        case Resource::Manifest:
         case Resource::TextTrack:
             // These resources are passive, but mixed usage is low enough that we
             // can block them in a mixed context.
@@ -530,6 +542,7 @@ bool ResourceFetcher::canRequest(Resource::Type type, const KURL& url, const Res
     case Resource::TextTrack:
     case Resource::ImportResource:
     case Resource::Media:
+    case Resource::Manifest:
         // By default these types of resources can be loaded from any origin.
         // FIXME: Are we sure about Resource::Font?
         if (originRestriction == FetchRequest::RestrictToSameOrigin && !securityOrigin->canRequest(url)) {
@@ -599,6 +612,7 @@ bool ResourceFetcher::canRequest(Resource::Type type, const KURL& url, const Res
     case Resource::Raw:
     case Resource::LinkPrefetch:
     case Resource::LinkSubresource:
+    case Resource::Manifest:
         break;
     case Resource::Media:
     case Resource::TextTrack: