When looking at this bug, I found at least the following issues:

1) PasswordManagerHandler was not canceling requests if new requests were made (by double-clicking the "Manage Saved Passwords..." button with a slow database - simulated with long Sleep).
2) PasswordStore starts its handle numbering at 0 meaning that the very first request is non-true and could hit DCHECK(s).
3) PasswordManagerHandler doesn't free the results.

When talking with the DOMUI TL (jhawkins) and an author of PasswordStore (stuartmorgan), I learned that it was modeled after HistoryService, which had since been refactored into a reusable suite of classes in content/browser/cancelable_request.h

So the CL will include fixes for the 3 issues, as well as a refactor to use the shared code in cancelable_requst.h

BUG=71466
TEST=chrome://settings/personal, then click "Manage Saved Passwords".  Put
PlatformThread::Sleep(10000), then try double-clicking the button to see no error.

Review URL: http://codereview.chromium.org/6646051

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@79625 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 4 insertions, 1 deletions

diff --git a/content/browser/cancelable_request.cc b/content/browser/cancelable_request.cc
index f1826fd..5e36d89 100644
--- a/content/browser/cancelable_request.cc
+++ b/content/browser/cancelable_request.cc
@@ -4,7 +4,8 @@
 
 #include "content/browser/cancelable_request.h"
 
-CancelableRequestProvider::CancelableRequestProvider() : next_handle_(1) {
+CancelableRequestProvider::CancelableRequestProvider()
+    : next_handle_(1) {
 }
 
 CancelableRequestProvider::~CancelableRequestProvider() {
@@ -28,6 +29,8 @@ CancelableRequestProvider::Handle CancelableRequestProvider::AddRequest(
     handle = next_handle_;
     pending_requests_[next_handle_] = request;
     ++next_handle_;
+    DCHECK(next_handle_)
+        << "next_handle_ may have wrapped around to invalid state.";
   }
 
   consumer->OnRequestAdded(this, handle);