Add GetEntryFromURL method to the ReadingListModel.

ios/chrome/browser/reading_list/reading_list_model_unittest.cc

 // Copyright 2016 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 "base/bind.h"
 #include "ios/chrome/browser/reading_list/reading_list_model_impl.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
@@ skipping 153 matching lines @@
   AssertObserverCount(0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1);
   EXPECT_EQ(0ul, model_->unread_size());
   EXPECT_EQ(1ul, model_->read_size());
   EXPECT_FALSE(model_->HasUnseenEntries());
 
   const ReadingListEntry& other_entry = model_->GetReadEntryAtIndex(0);
   EXPECT_EQ(GURL("http://example.com"), other_entry.URL());
   EXPECT_EQ("sample", other_entry.Title());
 }
 
+TEST_F(ReadingListModelTest, EntryFromURL) {
+  GURL url1("http://example.com");
+  GURL url2("http://example2.com");
+  std::string entry1_title = "foo bar qux";
+  model_->AddEntry(url1, entry1_title);
+
+  const ReadingListEntry* entry1 = model_->GetEntryFromURL(url1);
+  EXPECT_NE(nullptr, entry1);
+  EXPECT_EQ(entry1_title, entry1->Title());
+  model_->MarkReadByURL(url1);
+  entry1 = model_->GetEntryFromURL(url1);
+  EXPECT_NE(nullptr, entry1);
+  EXPECT_EQ(entry1_title, entry1->Title());
+
+  const ReadingListEntry* entry2 = model_->GetEntryFromURL(url2);
+  EXPECT_EQ(nullptr, entry2);
+}
+
 TEST_F(ReadingListModelTest, UnreadEntry) {
   // Setup.
   model_->AddEntry(GURL("http://example.com"), "sample");
   model_->MarkReadByURL(GURL("http://example.com"));
   ClearCounts();
   ASSERT_EQ(0ul, model_->unread_size());
   ASSERT_EQ(1ul, model_->read_size());
 
   // Action.
   model_->MarkUnreadByURL(GURL("http://example.com"));
@@ skipping 173 matching lines @@
 }
 
 // Tests that ReadingListModel calls CallbackModelBeingDeleted when destroyed.
 TEST_F(ReadingListModelTest, CallbackModelBeingDeleted) {
   AssertObserverCount(1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
   model_.reset();
   AssertObserverCount(1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0);
 }
 
 }  // namespace