Only wait for CancelAllRequests done if the post task succeeds

chrome/browser/history/android/sqlite_cursor.cc

Index: chrome/browser/history/android/sqlite_cursor.cc
diff --git a/chrome/browser/history/android/sqlite_cursor.cc b/chrome/browser/history/android/sqlite_cursor.cc
index 3a933c665afe21e89892dacd56b07fc7eccb0420..4bf584acd889f6630cb0261bae547dac0be91994 100644
--- a/chrome/browser/history/android/sqlite_cursor.cc
+++ b/chrome/browser/history/android/sqlite_cursor.cc
@@ -132,7 +132,17 @@ jint SQLiteCursor::GetColumnType(JNIEnv* env, jobject obj, jint 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,
@@ -150,25 +160,16 @@ SQLiteCursor::SQLiteCursor(const std::vector<std::string>& column_names,
 }
 
 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,
@@ -226,17 +227,6 @@ void SQLiteCursor::OnMoved(AndroidHistoryProviderService::Handle handle,
     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;