Revert "Remove webkit_glue::BuildUserAgent(), change the contract in webkit_glue"

content/common/content_client.h

Index: content/common/content_client.h
diff --git a/content/common/content_client.h b/content/common/content_client.h
index ad07400cf9a2604674e32003c960fc87ce6edc04..9f5521fee2c54382832cb8e7cd9067f3e89bbc33 100644
--- a/content/common/content_client.h
+++ b/content/common/content_client.h
@@ -76,10 +76,10 @@ class CONTENT_EXPORT ContentClient {
   // behalf of a swapped out renderer.
   virtual bool CanHandleWhileSwappedOut(const IPC::Message& msg) = 0;
 
-  // Returns the user agent and a flag indicating whether the returned
-  // string should always be used (if false, callers may override the
-  // value as needed to work around various user agent sniffing bugs).
-  virtual std::string GetUserAgent(bool *overriding) const = 0;
+  // Returns the user agent. If mimic_windows is true then the embedder can
+  // return a fake Windows user agent. This is a workaround for broken
+  // websites.
+  virtual std::string GetUserAgent(bool mimic_windows) const = 0;
 
   // Returns a string resource given its id.
   virtual string16 GetLocalizedString(int message_id) const = 0;