Transmit a X-Chrome-UMA-Enabled bit to Google domains from clients that have UMA enabled.

chrome/browser/google/google_util.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 //
 // Some Google related utility functions.
 
 #ifndef CHROME_BROWSER_GOOGLE_GOOGLE_UTIL_H__
 #define CHROME_BROWSER_GOOGLE_GOOGLE_UTIL_H__
 #pragma once
 
@@ skipping 28 matching lines @@
 // that has been assigned to a partner for reactivating a dormant chrome
 // install. Returns false if the information is not available.
 bool GetReactivationBrand(std::string* brand);
 
 // WARNING: The following IsGoogleXXX() functions use heuristics to rule out
 // "obviously false" answers.  They do NOT guarantee that the string in question
 // is actually on a Google-owned domain, just that it looks plausible.  If you
 // need to restrict some behavior to only happen on Google's officially-owned
 // domains, use TransportSecurityState::IsGooglePinnedProperty() instead.
 
-// True if |host| is "[www.]google.<TLD>" with a valid TLD.
-bool IsGoogleHostname(const std::string& host);
+// Designate whether or not a URL checking function also checks for specific
+// subdomains, or only "www" and empty subdomains.
+enum SubdomainPermission {
+  ALLOW_SUBDOMAIN,
+  DISALLOW_SUBDOMAIN,
+};
+
+// True if |url| is an HTTP[S] request with host "[www.]google.<TLD>" and no
+// explicit port. If |allow_subdomain| is true, we check against host

[MAD, 2012/04/17 18:16:28]

Maybe fix this comment to the new param type not being true/false anymore.

[SteveT, 2012/04/17 18:20:46]

Done.

+// "*.google.<TLD>" instead.
+bool IsGoogleDomainUrl(const std::string& url, SubdomainPermission permission);
+// True if |host| is "[www.]google.<TLD>" with a valid TLD. If
+// |allow_subdomain| is true, we check against host "*.google.<TLD>" instead.

[MAD, 2012/04/17 18:16:28]

Same here...

[SteveT, 2012/04/17 18:20:46]

Done.

+bool IsGoogleHostname(const std::string& host, SubdomainPermission permission);
 // True if |url| represents a valid Google home page URL.
 bool IsGoogleHomePageUrl(const std::string& url);
 // True if |url| represents a valid Google search URL.
 bool IsGoogleSearchUrl(const std::string& url);
 
 // True if a build is strictly organic, according to its brand code.
 bool IsOrganic(const std::string& brand);
 
 // True if a build should run as organic during first run. This uses
 // a slightly different set of brand codes from the standard IsOrganic
@@ skipping 11 matching lines @@
   ~BrandForTesting();
 
  private:
   std::string brand_;
   DISALLOW_COPY_AND_ASSIGN(BrandForTesting);
 };
 
 }  // namespace google_util
 
 #endif  // CHROME_BROWSER_GOOGLE_GOOGLE_UTIL_H__