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

webkit/glue/webkit_glue.h

 // Copyright (c) 2011 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.
 
 #ifndef WEBKIT_GLUE_WEBKIT_GLUE_H_
 #define WEBKIT_GLUE_WEBKIT_GLUE_H_
 
 #include "base/basictypes.h"
 
 #if defined(OS_WIN)
@@ skipping 70 matching lines @@
                   float page_height_in_pixels);
 
 // Returns a dump of the scroll position of the webframe.
 string16 DumpFrameScrollPosition(WebKit::WebFrame* web_frame, bool recursive);
 
 // Returns a dump of the given history state suitable for implementing the
 // dumpBackForwardList command of the layoutTestController.
 string16 DumpHistoryState(const std::string& history_state, int indent,
                           bool is_current);
 
-// Sets the user agent.  Pass true for overriding if this is a custom
-// user agent instead of the default one (in order to turn off any browser
-// sniffing workarounds). This must be called before GetUserAgent() can
-// be called.
-void SetUserAgent(const std::string& user_agent, bool overriding);
+// Called to override the default user agent with a custom one.  Call this
+// before anyone actually asks for the user agent in order to prevent
+// inconsistent behavior.
+void SetUserAgent(const std::string& new_user_agent);
 
-// Returns the user agent to use for the given URL. SetUserAgent() must
-// be called prior to calling this function.
+// Returns the user agent to use for the given URL, which is usually the
+// default user agent but may be overriden by a call to SetUserAgent() (which
+// should be done at startup).
 const std::string& GetUserAgent(const GURL& url);
 
 // Creates serialized state for the specified URL. This is a variant of
 // HistoryItemToString (in glue_serialize) that is used during session restore
 // if the saved state is empty.
 std::string CreateHistoryStateForURL(const GURL& url);
 
 // Removes any form data state from the history state string |content_state|.
 std::string RemoveFormDataFromHistoryState(const std::string& content_state);
 
@@ skipping 31 matching lines @@
     base::PlatformFileError error_code);
 
 // Returns a WebCanvas pointer associated with the given Skia canvas.
 WebKit::WebCanvas* ToWebCanvas(skia::PlatformCanvas*);
 
 // Returns the number of currently-active glyph pages this process is using.
 // There can be many such pages (maps of 256 character -> glyph) so this is
 // used to get memory usage statistics.
 int GetGlyphPageCount();
 
+// Construct the User-Agent header, filling in |result|.
+// - If mimic_windows is true, produce a fake Windows Chrome string.
+std::string BuildUserAgent(bool mimic_windows);
+
 //---- END FUNCTIONS IMPLEMENTED BY WEBKIT/GLUE -------------------------------
 
 
 //---- BEGIN FUNCTIONS IMPLEMENTED BY EMBEDDER --------------------------------
 
 // Glue to get resources from the embedder.
 
 // Gets a localized string given a message id.  Returns an empty string if the
 // message id is not found.
 string16 GetLocalizedString(int message_id);
@@ skipping 73 matching lines @@
 bool GetFontTable(int fd, uint32_t table, uint8_t* output,
                   size_t* output_length);
 #endif
 
 // ---- END FUNCTIONS IMPLEMENTED BY EMBEDDER ---------------------------------
 
 
 } // namespace webkit_glue
 
 #endif  // WEBKIT_GLUE_WEBKIT_GLUE_H_