Simplify the user agent overriding code, in preparation for moving it out of src/webkit.

webkit/common/user_agent/user_agent.cc

Index: webkit/common/user_agent/user_agent.cc
===================================================================
--- webkit/common/user_agent/user_agent.cc	(revision 255375)
+++ webkit/common/user_agent/user_agent.cc	(working copy)
@@ -6,10 +6,7 @@
 
 #include "base/lazy_instance.h"
 #include "base/logging.h"
-#include "base/strings/string_util.h"
-#include "base/strings/stringprintf.h"
 #include "base/synchronization/lock.h"
-#include "webkit/common/user_agent/user_agent_util.h"
 
 namespace webkit_glue {
 
@@ -20,16 +17,13 @@
   UserAgentState();
   ~UserAgentState();
 
-  void Set(const std::string& user_agent, bool overriding);
-  const std::string& Get(const GURL& url) const;
+  void Set(const std::string& user_agent);
+  const std::string& Get() const;
 
  private:
   mutable std::string user_agent_;
-  // The UA string when we're pretending to be Mac Safari or Win Firefox.
-  mutable std::string user_agent_for_spoofing_hack_;
 
   mutable bool user_agent_requested_;
-  bool user_agent_is_overridden_;
 
   // This object can be accessed from multiple threads, so use a lock around
   // accesses to the data members.
@@ -37,14 +31,13 @@
 };
 
 UserAgentState::UserAgentState()
-    : user_agent_requested_(false),
-      user_agent_is_overridden_(false) {
+    : user_agent_requested_(false) {
 }
 
 UserAgentState::~UserAgentState() {
 }
 
-void UserAgentState::Set(const std::string& user_agent, bool overriding) {
+void UserAgentState::Set(const std::string& user_agent) {
   base::AutoLock auto_lock(lock_);
   if (user_agent == user_agent_) {
     // We allow the user agent to be set multiple times as long as it
@@ -55,66 +48,15 @@
   DCHECK(!user_agent.empty());
   DCHECK(!user_agent_requested_) << "Setting the user agent after someone has "
       "already requested it can result in unexpected behavior.";
-  user_agent_is_overridden_ = overriding;
   user_agent_ = user_agent;
 }
 
-bool IsMicrosoftSiteThatNeedsSpoofingForSilverlight(const GURL& url) {
-#if defined(OS_MACOSX) && !defined(OS_IOS)
-  // The landing page for updating Silverlight gives a confusing experience
-  // in browsers that Silverlight doesn't officially support; spoof as
-  // Safari to reduce the chance that users won't complete updates.
-  // Should be removed if the sniffing is removed: http://crbug.com/88211
-  if (url.host() == "www.microsoft.com" &&
-      StartsWithASCII(url.path(), "/getsilverlight", false)) {
-    return true;
-  }
-#endif
-  return false;
-}
-
-bool IsYahooSiteThatNeedsSpoofingForSilverlight(const GURL& url) {
-#if defined(OS_MACOSX) && !defined(OS_IOS)
-  if ((url.host() == "downloads.yahoo.co.jp" &&
-      StartsWithASCII(url.path(), "/docs/silverlight/", true)) ||
-      url.host() == "gyao.yahoo.co.jp") {
-    return true;
-  }
-#elif defined(OS_WIN)
-  if (url.host() == "promotion.shopping.yahoo.co.jp") {
-    return true;
-  }
-#endif
-  return false;
-}
-
-const std::string& UserAgentState::Get(const GURL& url) const {
+const std::string& UserAgentState::Get() const {
   base::AutoLock auto_lock(lock_);
   user_agent_requested_ = true;
 
   DCHECK(!user_agent_.empty());
 
-  // Workarounds for sites that use misguided UA sniffing.
-  if (!user_agent_is_overridden_) {
-    if (IsMicrosoftSiteThatNeedsSpoofingForSilverlight(url) ||
-        IsYahooSiteThatNeedsSpoofingForSilverlight(url)) {
-      if (user_agent_for_spoofing_hack_.empty()) {
-#if defined(OS_MACOSX) && !defined(OS_IOS)
-        user_agent_for_spoofing_hack_ =
-            BuildUserAgentFromProduct("Version/5.1.1 Safari/534.51.22");
-#elif defined(OS_WIN)
-        // Pretend to be Firefox. Silverlight doesn't support Win Safari.
-        base::StringAppendF(
-            &user_agent_for_spoofing_hack_,
-            "Mozilla/5.0 (%s) Gecko/20100101 Firefox/8.0",
-            webkit_glue::BuildOSCpuInfo().c_str());
-#endif
-      }
-      DCHECK(!user_agent_for_spoofing_hack_.empty());
-      return user_agent_for_spoofing_hack_;
-    }
-  }
-
   return user_agent_;
 }
 
@@ -122,12 +64,12 @@
 
 }  // namespace
 
-void SetUserAgent(const std::string& user_agent, bool overriding) {
-  g_user_agent.Get().Set(user_agent, overriding);
+void SetUserAgent(const std::string& user_agent) {
+  g_user_agent.Get().Set(user_agent);
 }
 
 const std::string& GetUserAgent(const GURL& url) {
-  return g_user_agent.Get().Get(url);
+  return g_user_agent.Get().Get();
 }
 
 }  // namespace webkit_glue