android: fixs access to BookmarkModel from DataProvider

DataProvider::Query() is called from a background thread. BookmarkModel
isn't thread safe, and shouldn't be used from a background thread. This
code should go through bookmarks::ModelLoader and
bookmarks::HistoryBookmarkModel, which are thread safe.

BUG=1032172
TEST=none

Change-Id: I97dd97daed79d64e7ad28b3aa37bfadc0b7d9899
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1961216Reviewed-by: Donn Denman <donnd@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#723661}

chrome/browser/android/history_report/data_provider.cc

@@ -20,6 +20,7 @@
 #include "chrome/browser/history/history_service_factory.h"
 #include "chrome/browser/profiles/profile.h"
 #include "components/bookmarks/browser/bookmark_model.h"
+#include "components/bookmarks/browser/history_bookmark_model.h"
 #include "components/bookmarks/browser/model_loader.h"
 #include "components/bookmarks/browser/url_and_title.h"
 #include "components/history/core/browser/history_db_task.h"
@@ -102,11 +103,11 @@ namespace history_report {
 DataProvider::DataProvider(Profile* profile,
                            DeltaFileService* delta_file_service,
                            BookmarkModel* bookmark_model)
-    : bookmark_model_(bookmark_model),
-      delta_file_service_(delta_file_service) {
-  history_service_ = HistoryServiceFactory::GetForProfile(
-      profile, ServiceAccessType::EXPLICIT_ACCESS);
-}
+    : history_service_(HistoryServiceFactory::GetForProfile(
+          profile,
+          ServiceAccessType::EXPLICIT_ACCESS)),
+      bookmark_model_loader_(bookmark_model->model_loader()),
+      delta_file_service_(delta_file_service) {}
 
 DataProvider::~DataProvider() {}
 
@@ -127,8 +128,9 @@ std::unique_ptr<std::vector<DeltaFileEntryWithData>> DataProvider::Query(
                                     base::Unretained(&context),
                                     base::Unretained(entries.get())));
       std::vector<UrlAndTitle> bookmarks;
-      bookmark_model_->model_loader()->BlockTillLoaded();
-      bookmark_model_->GetBookmarks(&bookmarks);
+      bookmark_model_loader_->BlockTillLoaded();
+      bookmark_model_loader_->history_bookmark_model()->GetBookmarks(
+          &bookmarks);
       BookmarkMap bookmark_map;
       for (size_t i = 0; i < bookmarks.size(); ++i) {
         bookmark_map.insert(
@@ -187,12 +189,11 @@ void DataProvider::RecreateLog() {
   }
 
   std::vector<UrlAndTitle> bookmarks;
-  bookmark_model_->model_loader()->BlockTillLoaded();
-  bookmark_model_->GetBookmarks(&bookmarks);
+  bookmark_model_loader_->BlockTillLoaded();
+  bookmark_model_loader_->history_bookmark_model()->GetBookmarks(&bookmarks);
   urls.reserve(urls.size() + bookmarks.size());
-  for (size_t i = 0; i < bookmarks.size(); i++) {
+  for (size_t i = 0; i < bookmarks.size(); i++)
     urls.push_back(bookmarks[i].url.spec());
-  }
   delta_file_service_->Recreate(urls);
 }
 

chrome/browser/android/history_report/data_provider.h

@@ -11,6 +11,7 @@
 #include <vector>
 
 #include "base/macros.h"
+#include "base/memory/scoped_refptr.h"
 #include "base/task/cancelable_task_tracker.h"
 
 class Profile;
@@ -21,6 +22,7 @@ class HistoryService;
 
 namespace bookmarks {
 class BookmarkModel;
+class ModelLoader;
 }
 
 namespace history_report {
@@ -48,7 +50,7 @@ class DataProvider {
   void RecreateLog();
 
   history::HistoryService* history_service_;
-  bookmarks::BookmarkModel* bookmark_model_;
+  scoped_refptr<bookmarks::ModelLoader> bookmark_model_loader_;
   DeltaFileService* delta_file_service_;
   base::CancelableTaskTracker history_task_tracker_;