[Tests not passing yet] Remove prerender sessionStorage namespace merging.

chrome/browser/prerender/prerender_events.h

-// Copyright (c) 2013 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.
-
-#ifndef CHROME_BROWSER_PRERENDER_PRERENDER_EVENTS_H_
-#define CHROME_BROWSER_PRERENDER_PRERENDER_EVENTS_H_
-
-namespace prerender {
-
-// Events registered during prerendering used for debugging purposes and to
-// gather metrics.
-enum PrerenderEvent {
-  PRERENDER_EVENT_SWAPIN_NO_DELEGATE = 0,
-  PRERENDER_EVENT_SWAPIN_CANDIDATE = 1,
-  PRERENDER_EVENT_SWAPIN_CANDIDATE_NAMESPACE_MATCHES = 2,
-  PRERENDER_EVENT_SWAPIN_NO_MERGE_PENDING = 3,
-  PRERENDER_EVENT_SWAPIN_MERGING_DISABLED = 4,
-  PRERENDER_EVENT_SWAPIN_ISSUING_MERGE = 5,
-  PRERENDER_EVENT_MERGE_FOR_SWAPIN_CANDIDATE = 6,
-  PRERENDER_EVENT_MERGE_RESULT_NO_PENDING_SWAPIN = 7,
-  // Obsolete: PRERENDER_EVENT_MERGE_RESULT_TIMEOUT_CB = 8,
-  // Obsolete: PRERENDER_EVENT_MERGE_RESULT_RESULT_CB = 9,
-  PRERENDER_EVENT_MERGE_RESULT_TIMED_OUT = 10,
-  PRERENDER_EVENT_MERGE_RESULT_MERGE_DONE = 11,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_NAMESPACE_NOT_FOUND = 12,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_NAMESPACE_NOT_ALIAS = 13,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_NOT_LOGGING = 14,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_NO_TRANSACTIONS = 15,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_TOO_MANY_TRANSACTIONS = 16,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_NOT_MERGEABLE = 17,
-  PRERENDER_EVENT_MERGE_RESULT_RESULT_MERGEABLE = 18,
-  PRERENDER_EVENT_MERGE_RESULT_MERGE_FAILED = 19,
-  PRERENDER_EVENT_MERGE_RESULT_SWAPPING_IN = 20,
-  // Obsolete: PRERENDER_EVENT_MERGE_RESULT_SWAPIN_SUCCESSFUL = 21,
-  PRERENDER_EVENT_MERGE_RESULT_SWAPIN_FAILED = 22,
-  PRERENDER_EVENT_MAX,
-};
-
-// Return a human-readable name for |event|.
-const char* NameFromPrerenderEvent(PrerenderEvent event);
-
-}  // namespace prerender
-
-#endif  // CHROME_BROWSER_PRERENDER_PRERENDER_EVENTS_H_