Remove obviously unneeded forward declarations in chrome/browser/[abef]*/*.h.

chrome/browser/autocomplete/autocomplete.h

 // Copyright (c) 2010 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_AUTOCOMPLETE_AUTOCOMPLETE_H_
 #define CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_H_
 #pragma once
 
 #include <string>
 #include <vector>
@@ skipping 130 matching lines @@
 // ++: a series of matches with relevance from n up to (n + max_matches).
 // --: relevance score falls off over time (discounted 50 points @ 15 minutes,
 //     450 points @ two weeks)
 
 class AutocompleteInput;
 struct AutocompleteMatch;
 class AutocompleteProvider;
 class AutocompleteResult;
 class AutocompleteController;
 class HistoryContentsProvider;
-class KeywordProvider;
 class Profile;
 class TemplateURL;
 
 typedef std::vector<AutocompleteMatch> ACMatches;
 typedef std::vector<AutocompleteProvider*> ACProviders;
 
 // AutocompleteInput ----------------------------------------------------------
 
 // The user input for an autocomplete query.  Allows copying.
 class AutocompleteInput {
@@ skipping 727 matching lines @@
   AutocompleteInput::Type input_type;
   // Selected index (if selected) or -1 (AutocompletePopupModel::kNoMatch).
   size_t selected_index;
   // Inline autocompleted length (if displayed).
   size_t inline_autocompleted_length;
   // Result set.
   const AutocompleteResult& result;
 };
 
 #endif  // CHROME_BROWSER_AUTOCOMPLETE_AUTOCOMPLETE_H_