Remove implicit conversions from scoped_refptr to T* in c/b/chromeos/attestation

This patch was generated by running the rewrite_scoped_refptr clang tool
on a ChromeOS build.

BUG=110610

Review URL: https://codereview.chromium.org/567763003

Cr-Commit-Position: refs/heads/master@{#294909}

chrome/browser/chromeos/attestation/platform_verification_flow_unittest.cc

@@ -96,7 +96,7 @@ class FakeDelegate : public PlatformVerificationFlow::Delegate {
 
   virtual HostContentSettingsMap* GetContentSettings(
       content::WebContents* web_contents) OVERRIDE {
-    return content_settings_;
+    return content_settings_.get();
   }
 
   virtual bool IsGuestOrIncognito(content::WebContents* web_contents) OVERRIDE {