Extract chrome.runtime API code from extensions::EventRouter

extensions/browser/extensions_browser_client.h

Index: extensions/browser/extensions_browser_client.h
diff --git a/extensions/browser/extensions_browser_client.h b/extensions/browser/extensions_browser_client.h
index 467fd32969e6f54ba1dfd15fb4cac1d774b37c72..b99b3661d6b6d0d3f9d51fbe5c8215c2912685e3 100644
--- a/extensions/browser/extensions_browser_client.h
+++ b/extensions/browser/extensions_browser_client.h
@@ -11,8 +11,6 @@ class BrowserContext;
 
 namespace extensions {
 
-class ExtensionPrefs;
-
 // Interface to allow the extensions module to make browser-process-specific
 // queries of the embedder. Should be Set() once in the browser process.
 //
@@ -55,9 +53,9 @@ class ExtensionsBrowserClient {
 
   // Returns true if the client version has updated since the last run. Called
   // once each time the extensions system is loaded per browser_context. The
-  // implementation may wish to use |extension_prefs| to record the current
-  // version for later comparison. |extension_prefs| may be NULL in tests.
-  virtual bool DidVersionUpdate(ExtensionPrefs* extension_prefs) = 0;
+  // implementation may wish to use the BrowserContext to record the current
+  // version for later comparison.
+  virtual bool DidVersionUpdate(content::BrowserContext* context) = 0;
 
   // Returns the single instance of |this|.
   static ExtensionsBrowserClient* Get();