New Task Manager - Phase 1.3.2.B: Implement Tab Contents Task Providing (Prerender)

chrome/browser/task_management/providers/web_contents/prerender_tag.cc

Index: chrome/browser/task_management/providers/web_contents/prerender_tag.cc
diff --git a/chrome/browser/task_management/providers/web_contents/prerender_tag.cc b/chrome/browser/task_management/providers/web_contents/prerender_tag.cc
new file mode 100644
index 0000000000000000000000000000000000000000..bdc6c92d5699c2950b188551048ee31e2f8b02df
--- /dev/null
+++ b/chrome/browser/task_management/providers/web_contents/prerender_tag.cc
@@ -0,0 +1,22 @@
+// Copyright 2015 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/task_management/providers/web_contents/prerender_tag.h"
+#include "chrome/browser/task_management/providers/web_contents/web_contents_tags_manager.h"
+
+namespace task_management {
+
+PrerenderTask* PrerenderTag::CreateTask() const {
+  return new PrerenderTask(web_contents());
+}
+
+PrerenderTag::PrerenderTag(content::WebContents* web_contents)
+    : WebContentsTag(web_contents) {
+}
+
+PrerenderTag::~PrerenderTag() {
+  WebContentsTagsManager::GetInstance()->ClearFromProvider(this);

[ncarter (slow), 2015/06/19 19:50:51]

I was thinking that the ClearFromProvider() call would happen not here, but in
WebContentsTags::ClearTag, just before the user-data deletion? Is that workable?

The idea being, the provider shouldn't see double-deregistration of a tag, in
the scenario where the prerender webcontents is being deleted. It looks like the
code would DCHECK in that situation? You could test this by installing the real
taskprovider during one of the existing prerender tests that winds up with
FINAL_STATUS_CANCELLED.

[afakhry, 2015/06/19 21:49:22]

Done.

+}
+
+}  // namespace task_management