Fill the launcher with all found apps.

ui/app_list/search/history.cc

 // Copyright 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.
 
 #include "ui/app_list/search/history.h"
 
 #include <stddef.h>
 
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 10 matching lines @@
   TokenizedString tokenized(base::UTF8ToUTF16(utf8));
   return base::UTF16ToUTF8(
       base::JoinString(tokenized.tokens(), base::ASCIIToUTF16(" ")));
 }
 
 }  // namespace
 
 History::History(scoped_refptr<HistoryDataStore> store)
     : store_(store), data_loaded_(false) {
   const size_t kMaxQueryEntries = 1000;
-  const size_t kMaxSecondaryQueries = 5;
+  const size_t kMaxSecondaryQueries = 8;

[mtomasz, 2016/07/19 07:07:56]

(Not sure if this change is necessary.)

[Matt Giuca, 2016/07/19 07:29:10]

I don't know what this is and I don't think it's relevant. If you change it, you
should get xiyuan@ to look.

[xiyuan, 2016/07/19 15:22:55]

Matt is right that this is not relevant to what this CL tries to improve.
Applist search history remembers query -> launched-result mapping. It is a
one-to-many mapping. The primary one get boost score and we remember additional
launched results using the same query as secondary to get a less boost score.
And if a secondary result is launched using the query twice in a row, it is
promoted to primary. See [1]. This number must be greater than 2. 5 is somewhat
chosen arbitrarily. Changing to 8 probably will not get us more benefits but
will increase the history data size.

[1]:
https://cs.chromium.org/chromium/src/ui/app_list/search/history_data.h?rcl=14...

[mtomasz, 2016/07/20 00:46:48]

Removed. Done.

 
   data_.reset(
       new HistoryData(store_.get(), kMaxQueryEntries, kMaxSecondaryQueries));
   data_->AddObserver(this);
 }
 
 History::~History() {
   data_->RemoveObserver(this);
 }
 
@@ skipping 11 matching lines @@
     const std::string& query) const {
   DCHECK(IsReady());
   return data_->GetKnownResults(NormalizeString(query));
 }
 
 void History::OnHistoryDataLoadedFromStore() {
   data_loaded_ = true;
 }
 
 }  // namespace app_list