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

Source/core/loader/ManifestLoader.cpp

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "config.h"
+#include "ManifestLoader.h"
+
+#include "core/dom/Document.h"
+#include "core/fetch/FetchRequest.h"
+#include "core/fetch/ResourceFetcher.h"
+#include "core/html/HTMLLinkElement.h"
+#include "platform/network/ResourceRequest.h"
+#include "public/platform/WebManifest.h"
+#include "public/platform/WebManifestRequest.h"
+
+using namespace WebCore;
+
+void ManifestLoader::loadManifest(
+    blink::WebManifestRequest* request,
+    Document* document)
+{
+    // The object will self-destruct when done.
+    ManifestLoader* manifestLoader = new ManifestLoader(request);

[Nate Chapin, 2014/06/03 18:32:42]

Should this be an OwnPtr<> that gets leaked if we actually start the load?
PingLoader::start uses a method similar to this.

startLoading() would need to return a boolean, but we wouldn't need to have a
"delete this;" in every early-exit case in start loading.

[mlamouri (slow - plz ping), 2014/06/03 20:53:10]

I did something slightly different with OwnPtr<>(this) being instantiated on the
stack of ::startLoading() and ::notifyFinished() so |this| gets deleted when
those functions are left unless .leakPtr() is called.

+    manifestLoader->startLoading(document);
+}
+
+ManifestLoader::ManifestLoader(blink::WebManifestRequest* request)
+    : m_request(request)
+{
+    ASSERT(m_request);
+}
+
+ManifestLoader::~ManifestLoader()
+{
+}
+
+void ManifestLoader::startLoading(Document* document)
+{
+    ASSERT(document);
+
+    HTMLLinkElement* linkElement = document->linkManifest();
+    if (!linkElement) {
+        m_request->requestFailed(blink::WebManifestRequest::NoLinkManifest);
+        delete this;
+        return;
+    }
+
+    KURL url(document->baseURL(), linkElement->href(), document->encoding());
+    FetchRequest request = FetchRequest(ResourceRequest(url), FetchInitiatorInfo());
+    AtomicString crossOriginMode = linkElement->fastGetAttribute(HTMLNames::crossoriginAttr);
+    if (!crossOriginMode.isNull()) {

[Nate Chapin, 2014/06/03 18:32:42]

Nit: { } unnecessary.

[mlamouri (slow - plz ping), 2014/06/03 20:53:10]

Done.

+        request.setCrossOriginAccessControl(document->securityOrigin(), crossOriginMode);
+    }
+
+    ResourcePtr<Resource> resource = document->fetcher()->fetchManifest(request);
+    if (!resource) {
+        m_request->requestFailed(blink::WebManifestRequest::NetworkError);
+        delete this;
+        return;
+    }
+
+    setResource(resource);
+}
+
+void ManifestLoader::notifyFinished(Resource* resource)
+{
+    ASSERT(resource == this->resource());
+
+    if (resource->loadFailedOrCanceled() || resource->errorOccurred()) {
+        m_request->requestFailed(blink::WebManifestRequest::NetworkError);
+    } else {
+        // FIXME: parse the received data.
+        blink::WebManifest manifest;
+        m_request->requestSucceeded(manifest);
+    }
+
+    clearResource();
+    delete this;
+}