Code: void AppControllerImpl::SetClient(mojom::AppControllerClientPtr client) {
   client_ = std::move(client);
 }

Vulnerability Type: 
CWE ID: CWE-416
Summary: A heap use after free in PDFium in Google Chrome prior to 54.0.2840.59 for Windows, Mac, and Linux; 54.0.2840.85 for Android allows a remote attacker to potentially exploit heap corruption via crafted PDF files.
Commit Message: Refactor the AppController implementation into a KeyedService.

This is necessary to guarantee that the AppController will not outlive
the AppServiceProxy, which could happen before during Profile destruction.

Bug: 945427
Change-Id: I9e2089799e38d5a70a4a9aa66df5319113e7809e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1542336
Reviewed-by: Michael Giuffrida <michaelpg@chromium.org>
Commit-Queue: Lucas Tenório <ltenorio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#645122}