Inject the prodid for the extensions and component updaters.

components/update_client/configurator.h

Index: components/update_client/configurator.h
diff --git a/components/update_client/configurator.h b/components/update_client/configurator.h
index e547d955a8210e922a0066acf39489bf736b893f..1161ef45d336aead571cbe0a87c20923af868964 100644
--- a/components/update_client/configurator.h
+++ b/components/update_client/configurator.h
@@ -58,6 +58,11 @@ class Configurator : public base::RefCountedThreadSafe<Configurator> {
   // disabled. Similarly, these URLs have a fall back behavior too.
   virtual std::vector<GURL> PingUrl() const = 0;
 
+  // The ProdId is used as a prefix in some of the version strings which appear
+  // in the protocol requests. Possible values include "chrome", "chromecrx",
+  // "chromium", and "unknown".

[asargent_no_longer_on_chrome, 2016/09/15 15:58:47]

nit: looks like this can be "chromiumcrx" instead of (or in addition to)
"chromium"

https://cs.chromium.org/chromium/src/components/update_client/update_query_pa...

[Sorin Jianu, 2016/09/15 16:13:40]

Done.

+  virtual std::string GetProdId() const = 0;
+
   // Version of the application. Used to compare the component manifests.
   virtual base::Version GetBrowserVersion() const = 0;