Implement ManifestFetcher, helper to fetch Web Manifests.

chrome/renderer/net/net_error_helper.cc

Index: chrome/renderer/net/net_error_helper.cc
diff --git a/chrome/renderer/net/net_error_helper.cc b/chrome/renderer/net/net_error_helper.cc
index 0e75c0613bbfe1d79fd4f83fc6b3333b593b5c2d..3a85b2dbf06cea424e44cf5fcb93eb0395573122 100644
--- a/chrome/renderer/net/net_error_helper.cc
+++ b/chrome/renderer/net/net_error_helper.cc
@@ -264,6 +264,7 @@ void NetErrorHelper::FetchNavigationCorrections(
       frame,
       blink::WebURLRequest::RequestContextInternal,
       blink::WebURLRequest::FrameTypeTopLevel,
+      content::ResourceFetcher::PLATFORM_LOADER,
       base::Bind(&NetErrorHelper::OnNavigationCorrectionsFetched,
                  base::Unretained(this)));
 
@@ -293,6 +294,7 @@ void NetErrorHelper::SendTrackingRequest(
       frame,
       blink::WebURLRequest::RequestContextInternal,
       blink::WebURLRequest::FrameTypeTopLevel,
+      content::ResourceFetcher::PLATFORM_LOADER,
       base::Bind(&NetErrorHelper::OnTrackingRequestComplete,
                  base::Unretained(this)));
 }