Only wait for CancelAllRequests done if the post task succeeds

chrome/browser/history/android/sqlite_cursor.cc

 // Copyright (c) 2012 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 "chrome/browser/history/android/sqlite_cursor.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/bind.h"
@@ skipping 114 matching lines @@
 
   event_.Wait();
   return position_;
 }
 
 jint SQLiteCursor::GetColumnType(JNIEnv* env, jobject obj, jint column) {
   return GetColumnTypeInternal(column);
 }
 
 void SQLiteCursor::Destroy(JNIEnv* env, jobject obj) {
-  delete this;
+  // We do our best to cleanup when Destroy() is called from Java's finalize()
+  // where the UI message loop might stop running or in the process of shutting
+  // down, as the whole process will be destroyed soon, it's fine to leave some
+  // objects out there.
+  if (BrowserThread::CurrentlyOn(BrowserThread::UI)) {
+    DestroyOnUIThread();
+  } else if (!BrowserThread::PostTask(BrowserThread::UI, FROM_HERE,
+                 base::Bind(&SQLiteCursor::DestroyOnUIThread,
+                     base::Unretained(this)))) {
+    delete this;
+  }
 }
 
 SQLiteCursor::SQLiteCursor(const std::vector<std::string>& column_names,
                            history::AndroidStatement* statement,
                            AndroidHistoryProviderService* service,
                            FaviconService* favicon_service)
     : position_(-1),
       event_(false, false),
       statement_(statement),
       column_names_(column_names),
       service_(service),
       favicon_service_(favicon_service),
       count_(-1),
       test_observer_(NULL) {
 }
 
 SQLiteCursor::~SQLiteCursor() {
+}
+
+void SQLiteCursor::DestroyOnUIThread() {
   // Consumer requests were set in the UI thread. They must be cancelled
   // using the same thread.
-  if (BrowserThread::CurrentlyOn(BrowserThread::UI)) {
-    CancelAllRequests(NULL);
-  } else {
-    base::WaitableEvent event(false, false);
-    BrowserThread::PostTask(
-        BrowserThread::UI,
-        FROM_HERE,
-        base::Bind(&SQLiteCursor::CancelAllRequests, base::Unretained(this),
-                   &event));
-    event.Wait();
-  }
-
-  BrowserThread::PostTask(
-      BrowserThread::UI,
-      FROM_HERE,
-      base::Bind(&AndroidHistoryProviderService::CloseStatement,
-                 base::Unretained(service_), statement_));
+  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
+  consumer_.reset();
+  tracker_.reset();
+  service_->CloseStatement(statement_);
+  delete this;
 }
 
 bool SQLiteCursor::GetFavicon(chrome::FaviconID id,
                               std::vector<unsigned char>* image_data) {
   if (id) {
     BrowserThread::PostTask(
         BrowserThread::UI,
         FROM_HERE,
         base::Bind(&SQLiteCursor::GetFaviconForIDInUIThread,
                    base::Unretained(this), id,
@@ skipping 37 matching lines @@
 
 void SQLiteCursor::OnMoved(AndroidHistoryProviderService::Handle handle,
                            int pos) {
   position_ = pos;
   event_.Signal();
   if (test_observer_)
     // Notified test_observer on UI thread instead of the one it will wait.
     test_observer_->OnGetMoveToResult();
 }
 
-void SQLiteCursor::CancelAllRequests(base::WaitableEvent* finished) {
-  DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
-
-  // Destruction will cancel all pending tasks.
-  consumer_.reset();
-  tracker_.reset();
-
-  if (finished)
-    finished->Signal();
-}
-
 SQLiteCursor::JavaColumnType SQLiteCursor::GetColumnTypeInternal(int column) {
   if (column == statement_->favicon_index())
     return SQLiteCursor::BLOB;
 
   return ToJavaColumnType(statement_->statement()->ColumnType(column));
 }
 
 void SQLiteCursor::RunMoveStatementOnUIThread(int pos) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   if (!consumer_.get())
     consumer_.reset(new CancelableRequestConsumer());
   service_->MoveStatement(
       statement_, position_, pos, consumer_.get(),
       base::Bind(&SQLiteCursor::OnMoved, base::Unretained(this)));
 }