New link rel=prerender api, using WebKit::WebPrerenderingPlatform

chrome/renderer/prerender/prerenderer_client.cc

+// Copyright (c) 2012 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 "chrome/renderer/prerender/prerenderer_client.h"
+
+#include "chrome/renderer/prerender/prerender_extra_data.h"
+#include "content/public/renderer/render_view.h"
+#include "third_party/WebKit/Source/WebKit/chromium/public/WebView.h"
+
+namespace {

[cbentzel, 2012/05/04 15:32:25]

Nit: you could probably write this as

namespace {
static int s_last_prerender_id = 0;
}

instead of lots of vertical space.

[gavinp, 2012/05/04 23:10:51]

Done.

+
+static int s_last_prerender_id = 0;
+
+}  // end namespace
+
+namespace prerender {
+
+PrerendererClient::PrerendererClient(content::RenderView* render_view)
+    : content::RenderViewObserver(render_view) {
+  DVLOG(5) << "PrerendererClient::PrerendererClient()";
+  if (render_view)  // NULL in unit tests.
+    render_view->GetWebView()->setPrerendererClient(this);
+}
+
+PrerendererClient::~PrerendererClient() {
+}
+
+void PrerendererClient::willAddPrerender(
+    WebKit::WebPrerender* prerender) {
+  DVLOG(3) << "PrerendererClient::willAddPrerender url = "
+           << prerender->url().spec().data();
+  prerender->setExtraData(new PrerenderExtraData(++s_last_prerender_id,
+                                                 routing_id(),
+                                                 render_view()->GetSize()));

[cbentzel, 2012/05/04 15:32:25]

Why is render_view() always guaranteed to be non-NULL? Is it due to the NULL
check in the PrerenderClient constructor?

[gavinp, 2012/05/04 23:10:51]

It's guaranteed to be non-null because the only caller is in WebKit, and the
only way WebKit can find it is through the set call above.  But, even more to
the point, there are no unit tests with a PrerendererClient in them, anyway, so
that comment (which was copied from another constructor of a filter) is
misleading.  I've removed that check on the render_view in the constructor, and
replaced it with a DCHECK.

+}
+
+}  // namespace prerender
+