Remove unused DownloadQuery::Skip().

It was originally used for the downloads page to load only
some items, but ended up not being necessary.

This is essentially a revert of crrev.com/356506

R=asanka@chromium.org
BUG=526577

Review URL: https://codereview.chromium.org/1566593002

Cr-Commit-Position: refs/heads/master@{#367750}

3 files changed, 6 insertions, 51 deletions

diff --git a/chrome/browser/download/download_query.cc b/chrome/browser/download/download_query.cc
index f42e93d..a1819f3 100644
--- a/chrome/browser/download/download_query.cc
+++ b/chrome/browser/download/download_query.cc
@@ -242,8 +242,7 @@ bool DownloadQuery::MatchesQuery(const std::vector<base::string16>& query_terms,
   return true;
 }
 
-DownloadQuery::DownloadQuery()
-    : limit_(std::numeric_limits<uint32_t>::max()), skip_(0U) {}
+DownloadQuery::DownloadQuery() : limit_(std::numeric_limits<uint32_t>::max()) {}
 DownloadQuery::~DownloadQuery() {}
 
 // AddFilter() pushes a new FilterCallback to filters_. Most FilterCallbacks are
@@ -435,21 +434,13 @@ void DownloadQuery::AddSorter(DownloadQuery::SortType type,
 }
 
 void DownloadQuery::FinishSearch(DownloadQuery::DownloadVector* results) const {
-  if (skip_ >= results->size()) {
-    results->clear();
-    return;
+ if (!sorters_.empty()) {
+    std::partial_sort(results->begin(),
+                      results->begin() + std::min(limit_, results->size()),
+                      results->end(),
+                      DownloadComparator(sorters_));
   }
 
-  if (!sorters_.empty()) {
-    std::partial_sort(
-        results->begin(),
-        results->begin() + std::min(limit_ + skip_, results->size()),
-        results->end(),
-        DownloadComparator(sorters_));
-  }
-
-  results->erase(results->begin(), results->begin() + skip_);
-
   if (results->size() > limit_)
     results->resize(limit_);
 }
diff --git a/chrome/browser/download/download_query.h b/chrome/browser/download/download_query.h
index e81edc5..980e531 100644
--- a/chrome/browser/download/download_query.h
+++ b/chrome/browser/download/download_query.h
@@ -39,7 +39,6 @@ class Value;
 // query.AddSorter(SORT_BYTES_RECEIVED, ASCENDING);
 // query.AddSorter(SORT_URL, DESCENDING);
 // query.Limit(20);
-// query.Skip(5);
 // DownloadVector all_items, results;
 // query.Search(all_items.begin(), all_items.end(), &results);
 class DownloadQuery {
@@ -128,11 +127,6 @@ class DownloadQuery {
   // Limit the size of search results to |limit|.
   void Limit(size_t limit) { limit_ = limit; }
 
-  // Ignore |skip| items. Note: which items are skipped are not guaranteed to
-  // always be the same. If you rely on this, you should probably be using
-  // AddSorter() in conjunction with this method.
-  void Skip(size_t skip) { skip_ = skip; }
-
   // Filters DownloadItem*s from |iter| to |last| into |results|, sorts
   // |results|, and limits the size of |results|. |results| must be non-NULL.
   template <typename InputIterator>
@@ -160,7 +154,6 @@ class DownloadQuery {
   FilterCallbackVector filters_;
   SorterVector sorters_;
   size_t limit_;
-  size_t skip_;
 
   DISALLOW_COPY_AND_ASSIGN(DownloadQuery);
 };
diff --git a/chrome/browser/download/download_query_unittest.cc b/chrome/browser/download/download_query_unittest.cc
index 8ffc90a..37fba0c 100644
--- a/chrome/browser/download/download_query_unittest.cc
+++ b/chrome/browser/download/download_query_unittest.cc
@@ -182,35 +182,6 @@ TEST_F(DownloadQueryTest, DownloadQueryTest_Limit) {
   ExpectStandardFilterResults();
 }
 
-TEST_F(DownloadQueryTest, DownloadQueryTest_Skip) {
-  CreateMocks(2);
-  query()->Skip(1);
-  Search();
-  EXPECT_EQ(1U, results()->size());
-}
-
-TEST_F(DownloadQueryTest, DownloadQueryTest_SkipMoreThanExist) {
-  query()->Skip(20);
-  Search();
-  EXPECT_EQ(0U, results()->size());
-}
-
-TEST_F(DownloadQueryTest, DownloadQueryTest_LimitSkipAndSort) {
-  const size_t kNumMocks = 10U;
-  CreateMocks(kNumMocks);
-  for (size_t i = 0; i < kNumMocks; ++i) {
-    EXPECT_CALL(mock(i), GetStartTime()).WillRepeatedly(Return(
-        base::Time::FromTimeT(kSomeKnownTime + 1000 * i)));
-  }
-  query()->AddSorter(DownloadQuery::SORT_START_TIME, DownloadQuery::ASCENDING);
-  query()->Limit(2);
-  query()->Skip(5);
-  Search();
-  EXPECT_EQ(2U, results()->size());
-  EXPECT_EQ(5U, results()->at(0)->GetId());
-  EXPECT_EQ(6U, results()->at(1)->GetId());
-}
-
 TEST_F(DownloadQueryTest, DownloadQueryTest_FilterGenericQueryFilename) {
   CreateMocks(2);
   EXPECT_CALL(mock(0), GetBrowserContext()).WillRepeatedly(Return(