Handle interface to prerenders.

chrome/browser/prerender/prerender_handle.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/browser/prerender/prerender_handle.h"
+
+#include <algorithm>
+
+#include "chrome/browser/prerender/prerender_contents.h"
+
+namespace prerender {
+
+PrerenderHandle::~PrerenderHandle() {
+  OnCancel();
+}
+
+void PrerenderHandle::OnNavigateAway() {
+  DCHECK(CalledOnValidThread());

[dominich, 2012/07/12 16:16:48]

worth a DCHECK(IsValid());?

+  if (!prerender_data_)
+    return;
+  prerender_data_->OnNavigateAway();
+  prerender_data_.reset();
+}
+
+void PrerenderHandle::OnCancel() {
+  DCHECK(CalledOnValidThread());

[dominich, 2012/07/12 16:16:48]

worth a DCHECK(IsValid());?

[gavinp, 2012/07/13 12:02:22]

Done, and I slightly changed the semantics around these handles: you now must
call ONE OF OnCancel() or OnNavigateAway() before destruction, and you can't
call these methods twice. 

+  if (!prerender_data_)
+    return;
+
+  prerender_data_->OnCancel();
+  prerender_data_.reset();
+}
+
+bool PrerenderHandle::IsValid() const {
+  return prerender_data_ != NULL;
+}
+
+bool PrerenderHandle::IsPending() const {
+  DCHECK(CalledOnValidThread());
+  return prerender_data_ && !prerender_data_->contents();
+}
+
+bool PrerenderHandle::IsPrerendering() const {
+  DCHECK(CalledOnValidThread());
+  return prerender_data_ && prerender_data_->contents();
+}
+
+bool PrerenderHandle::IsFinishedLoading() const {
+  DCHECK(CalledOnValidThread());
+  if (!prerender_data_ || IsPending())
+    return false;
+  return prerender_data_->contents()->has_finished_loading();
+}
+
+PrerenderHandle::PrerenderHandle(
+    PrerenderManager::PrerenderData* prerender_data)
+    : prerender_data_(prerender_data->AsWeakPtr()),
+      weak_ptr_factory_(this) {
+  prerender_data->OnNewHandle();
+}
+
+void PrerenderHandle::SwapPrerenderDataWith(
+    PrerenderHandle* other_prerender_handle) {
+  DCHECK(CalledOnValidThread());
+  DCHECK(other_prerender_handle);
+  std::swap(prerender_data_, other_prerender_handle->prerender_data_);
+}
+
+}  // namespace prerender