[iOS] Upstream BrowsingDataRemoverHelper.

BrowsingDataRemoverHelper is an helper class that serializes usage of
IOSChromeBrowsingDataRemover methods as they are not reentrant.

BUG=None

Review URL: https://codereview.chromium.org/1778353003

Cr-Commit-Position: refs/heads/master@{#380424}

6 files changed, 183 insertions, 8 deletions

diff --git a/ios/chrome/browser/BUILD.gn b/ios/chrome/browser/BUILD.gn
index f0ee057..84a5d34 100644
--- a/ios/chrome/browser/BUILD.gn
+++ b/ios/chrome/browser/BUILD.gn
@@ -85,7 +85,11 @@ source_set("browser") {
     "browser_state/off_the_record_chrome_browser_state_io_data.mm",
     "browser_state_metrics/browser_state_metrics.cc",
     "browser_state_metrics/browser_state_metrics.h",
-    "browsing_data_change_listening.h",
+    "browsing_data/browsing_data_change_listening.h",
+    "browsing_data/browsing_data_remover_helper.cc",
+    "browsing_data/browsing_data_remover_helper.h",
+    "browsing_data/ios_chrome_browsing_data_remover.h",
+    "browsing_data/ios_chrome_browsing_data_remover.mm",
     "chrome_constants.cc",
     "chrome_constants.h",
     "chrome_paths.h",
diff --git a/ios/chrome/browser/browsing_data_change_listening.h b/ios/chrome/browser/browsing_data/browsing_data_change_listening.h
index 2c0afe8..ca5284a 100644
--- a/ios/chrome/browser/browsing_data_change_listening.h
+++ b/ios/chrome/browser/browsing_data/browsing_data_change_listening.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef IOS_CHROME_BROWSER_BROWSING_DATA_CHANGE_LISTENING_H_
-#define IOS_CHROME_BROWSER_BROWSING_DATA_CHANGE_LISTENING_H_
+#ifndef IOS_CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_CHANGE_LISTENING_H_
+#define IOS_CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_CHANGE_LISTENING_H_
 
 // Listener for changes in browsing data.
 @protocol BrowsingDataChangeListening
@@ -11,4 +11,4 @@
 - (void)didChangeCookieStorage;
 @end
 
-#endif  // IOS_CHROME_BROWSER_BROWSING_DATA_CHANGE_LISTENING_H_
+#endif  // IOS_CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_CHANGE_LISTENING_H_
diff --git a/ios/chrome/browser/browsing_data/browsing_data_remover_helper.cc b/ios/chrome/browser/browsing_data/browsing_data_remover_helper.cc
new file mode 100644
index 0000000..3df5741
--- /dev/null
+++ b/ios/chrome/browser/browsing_data/browsing_data_remover_helper.cc
@@ -0,0 +1,98 @@
+// 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 "ios/chrome/browser/browsing_data/browsing_data_remover_helper.h"
+
+#include <utility>
+
+#include "ios/chrome/browser/browser_state/chrome_browser_state.h"
+
+BrowsingDataRemoverHelper::BrowsingDataRemoverHelper()
+    : current_remover_(nullptr) {}
+
+BrowsingDataRemoverHelper::~BrowsingDataRemoverHelper() {
+  DCHECK(pending_removals_.empty());
+}
+
+BrowsingDataRemoverHelper::BrowsingDataRemovalInfo::BrowsingDataRemovalInfo(
+    int remove_mask,
+    const base::Closure& callback)
+    : remove_mask(remove_mask) {
+  callbacks.push_back(callback);
+}
+
+BrowsingDataRemoverHelper::BrowsingDataRemovalInfo::~BrowsingDataRemovalInfo() {
+}
+
+void BrowsingDataRemoverHelper::Remove(ios::ChromeBrowserState* browser_state,
+                                       int remove_mask,
+                                       const base::Closure& callback) {
+  DCHECK(browser_state);
+  DCHECK(!browser_state->IsOffTheRecord());
+  // IOSChromeBrowsingDataRemover::Callbacks are called before
+  // OnIOSChromeBrowsingDataRemoverDone() and after
+  // IOSChromeBrowsingDataRemover::is_removing() is set to false. In this
+  // window, |current_remover_| needs to be checked as well.
+  if (current_remover_ || IOSChromeBrowsingDataRemover::is_removing()) {
+    // IOSChromeBrowsingDataRemover is not re-entrant. If it is already running,
+    // add the browser_state to |pending_removals_| for later deletion. If the
+    // browser_state is already scheduled for removal of browsing data, update
+    // the remove mask and callbacks.
+    DCHECK(current_remover_);
+    auto pending_removals_iter = pending_removals_.find(browser_state);
+    if (pending_removals_iter == pending_removals_.end()) {
+      scoped_ptr<BrowsingDataRemovalInfo> removal_info(
+          new BrowsingDataRemovalInfo(remove_mask, callback));
+      pending_removals_[browser_state] = std::move(removal_info);
+    } else {
+      pending_removals_iter->second->remove_mask |= remove_mask;
+      pending_removals_iter->second->callbacks.push_back(callback);
+    }
+  } else {
+    scoped_ptr<BrowsingDataRemovalInfo> removal_info(
+        new BrowsingDataRemovalInfo(remove_mask, callback));
+    DoRemove(browser_state, std::move(removal_info));
+  }
+}
+
+void BrowsingDataRemoverHelper::OnIOSChromeBrowsingDataRemoverDone() {
+  current_remover_ = nullptr;
+
+  DCHECK(current_removal_info_);
+  // Inform clients of the currently finished removal operation that browsing
+  // data was removed.
+  for (const auto& callback : current_removal_info_->callbacks) {
+    if (!callback.is_null()) {
+      callback.Run();
+    }
+  }
+  current_removal_info_.reset();
+
+  if (pending_removals_.empty())
+    return;
+
+  ios::ChromeBrowserState* next_browser_state =
+      pending_removals_.begin()->first;
+  scoped_ptr<BrowsingDataRemovalInfo> removal_info =
+      std::move(pending_removals_[next_browser_state]);
+  pending_removals_.erase(next_browser_state);
+  DoRemove(next_browser_state, std::move(removal_info));
+}
+
+void BrowsingDataRemoverHelper::DoRemove(
+    ios::ChromeBrowserState* browser_state,
+    scoped_ptr<BrowsingDataRemovalInfo> removal_info) {
+  DCHECK(!current_remover_ && !IOSChromeBrowsingDataRemover::is_removing());
+
+  current_removal_info_ = std::move(removal_info);
+
+  // IOSChromeBrowsingDataRemover deletes itself.
+  IOSChromeBrowsingDataRemover* remover =
+      IOSChromeBrowsingDataRemover::CreateForPeriod(
+          browser_state, IOSChromeBrowsingDataRemover::EVERYTHING);
+  remover->AddObserver(this);
+  current_remover_ = remover;
+  int remove_mask = current_removal_info_->remove_mask;
+  remover->Remove(remove_mask);
+}
diff --git a/ios/chrome/browser/browsing_data/browsing_data_remover_helper.h b/ios/chrome/browser/browsing_data/browsing_data_remover_helper.h
new file mode 100644
index 0000000..9ae632a
--- /dev/null
+++ b/ios/chrome/browser/browsing_data/browsing_data_remover_helper.h
@@ -0,0 +1,71 @@
+// 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.
+
+#ifndef IOS_CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_REMOVER_HELPER_H_
+#define IOS_CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_REMOVER_HELPER_H_
+
+#include <map>
+#include <vector>
+
+#include "base/callback.h"
+#include "base/memory/scoped_ptr.h"
+#include "ios/chrome/browser/browsing_data/ios_chrome_browsing_data_remover.h"
+
+namespace ios {
+class ChromeBrowserState;
+}
+
+// A helper class that serializes execution of IOSChromeBrowsingDataRemover
+// methods since the IOSChromeBrowsingDataRemover APIs are not re-entrant.
+class BrowsingDataRemoverHelper
+    : public IOSChromeBrowsingDataRemover::Observer {
+ public:
+  BrowsingDataRemoverHelper();
+  ~BrowsingDataRemoverHelper() override;
+
+  // Removes the specified browsing data associated with |browser_state|. Calls
+  // |callback| when the browsing data is actually removed. |browser_state|
+  // cannot be null and must not be off the record.
+  // |callback| is called on the main thread.
+  // Note: Removal operations are not necessarily processed in the sequence that
+  // they are received in.
+  void Remove(ios::ChromeBrowserState* browser_state,
+              int remove_mask,
+              const base::Closure& callback);
+
+ private:
+  // Encapsulates the information that is needed to remove browsing data from
+  // a ChromeBrowserState.
+  struct BrowsingDataRemovalInfo {
+    // Creates a BrowsingDataRemovalInfo with a single callback |callback|.
+    BrowsingDataRemovalInfo(int remove_mask, const base::Closure& callback);
+    ~BrowsingDataRemovalInfo();
+    // The mask of all the types of browsing data that needs to be removed.
+    // Obtained from BrowsingDataRemoved::RemoveDataMask.
+    int remove_mask;
+    // The vector of callbacks that need to be run when browsing data is
+    // actually removed.
+    std::vector<base::Closure> callbacks;
+  };
+
+  // IOSChromeBrowsingDataRemover::Observer methods.
+  void OnIOSChromeBrowsingDataRemoverDone() override;
+
+  // Removes the browsing data using IOSChromeBrowsingDataRemover.
+  // IOSChromeBrowsingDataRemover
+  // must not be running.
+  void DoRemove(ios::ChromeBrowserState* browser_state,
+                scoped_ptr<BrowsingDataRemovalInfo> removal_info);
+
+  // A map that contains the all the ChromeBrowserStates that have a removal
+  // operation pending along with their associated BrowsingDataRemovalInfo.
+  std::map<ios::ChromeBrowserState*, scoped_ptr<BrowsingDataRemovalInfo>>
+      pending_removals_;
+  // The BrowsingDataRemovalInfo of the currently enqueued removal operation.
+  scoped_ptr<BrowsingDataRemovalInfo> current_removal_info_;
+  // The actual object that perfoms the removal of browsing data.
+  IOSChromeBrowsingDataRemover* current_remover_;
+};
+
+#endif  // IOS_CHROME_BROWSER_BROWSING_DATA_BROWSING_DATA_REMOVER_HELPER_H_
diff --git a/ios/chrome/browser/net/chrome_cookie_store_ios_client.mm b/ios/chrome/browser/net/chrome_cookie_store_ios_client.mm
index 9d0e74b..d3b8235 100644
--- a/ios/chrome/browser/net/chrome_cookie_store_ios_client.mm
+++ b/ios/chrome/browser/net/chrome_cookie_store_ios_client.mm
@@ -5,7 +5,7 @@
 #include "ios/chrome/browser/net/chrome_cookie_store_ios_client.h"
 
 #include "base/logging.h"
-#import "ios/chrome/browser/browsing_data_change_listening.h"
+#import "ios/chrome/browser/browsing_data/browsing_data_change_listening.h"
 #include "ios/web/public/web_thread.h"
 
 ChromeCookieStoreIOSClient::ChromeCookieStoreIOSClient(
diff --git a/ios/chrome/ios_chrome.gyp b/ios/chrome/ios_chrome.gyp
index d6dd668..50d18a7 100644
--- a/ios/chrome/ios_chrome.gyp
+++ b/ios/chrome/ios_chrome.gyp
@@ -220,9 +220,11 @@
         'browser/browser_state/off_the_record_chrome_browser_state_io_data.mm',
         'browser/browser_state_metrics/browser_state_metrics.cc',
         'browser/browser_state_metrics/browser_state_metrics.h',
+        'browser/browsing_data/browsing_data_change_listening.h',
+        'browser/browsing_data/browsing_data_remover_helper.cc',
+        'browser/browsing_data/browsing_data_remover_helper.h',
         'browser/browsing_data/ios_chrome_browsing_data_remover.h',
         'browser/browsing_data/ios_chrome_browsing_data_remover.mm',
-        'browser/browsing_data_change_listening.h',
         'browser/chrome_constants.cc',
         'browser/chrome_constants.h',
         'browser/chrome_paths.h',
@@ -659,10 +661,10 @@
         'browser/variations/ios_chrome_variations_service_client.h',
         'browser/web/dom_altering_lock.h',
         'browser/web/dom_altering_lock.mm',
-        'browser/web/web_view_type_util.h',
-        'browser/web/web_view_type_util.mm',
         'browser/web/resubmit_data_controller.h',
         'browser/web/resubmit_data_controller.mm',
+        'browser/web/web_view_type_util.h',
+        'browser/web/web_view_type_util.mm',
         'browser/web_data_service_factory.cc',
         'browser/web_data_service_factory.h',
         'browser/web_resource/web_resource_util.cc',