Add asserts to TestingProfile::CreateHistoryService to ensure files are deleted

chrome/test/base/testing_profile.cc

Index: chrome/test/base/testing_profile.cc
diff --git a/chrome/test/base/testing_profile.cc b/chrome/test/base/testing_profile.cc
index e35899875925ed2d5b97e524fe9524cd83d342be..88f0316b27daa4f57dd51a1cf02d73a73c2e8a9b 100644
--- a/chrome/test/base/testing_profile.cc
+++ b/chrome/test/base/testing_profile.cc
@@ -354,12 +354,15 @@ static BrowserContextKeyedService* BuildHistoryService(
   return new HistoryService(static_cast<Profile*>(profile));
 }
 
-void TestingProfile::CreateHistoryService(bool delete_file, bool no_db) {
+bool TestingProfile::CreateHistoryService(bool delete_file, bool no_db) {
   DestroyHistoryService();
   if (delete_file) {
     base::FilePath path = GetPath();
     path = path.Append(chrome::kHistoryFilename);
-    base::DeleteFile(path, false);
+    if (!base::DeleteFile(path, false) ||
+        base::PathExists(path)) {
+      return false;
+    }
   }
   // This will create and init the history service.
   HistoryService* history_service = static_cast<HistoryService*>(
@@ -372,6 +375,7 @@ void TestingProfile::CreateHistoryService(bool delete_file, bool no_db) {
   }
   // Disable WebHistoryService by default, since it makes network requests.
   WebHistoryServiceFactory::GetInstance()->SetTestingFactory(this, NULL);
+  return true;
 }
 
 void TestingProfile::DestroyHistoryService() {