Support loading trial tokens from HTTP headers.

third_party/WebKit/Source/core/loader/FrameLoader.cpp

Index: third_party/WebKit/Source/core/loader/FrameLoader.cpp
diff --git a/third_party/WebKit/Source/core/loader/FrameLoader.cpp b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
index 9026d06f4a4fb40b5a55a9610ba61fa729e19756..55f2ca8a4b9156586ff6dddf0754bc904037f1bb 100644
--- a/third_party/WebKit/Source/core/loader/FrameLoader.cpp
+++ b/third_party/WebKit/Source/core/loader/FrameLoader.cpp
@@ -74,6 +74,7 @@
 #include "core/loader/NetworkHintsInterface.h"
 #include "core/loader/ProgressTracker.h"
 #include "core/loader/appcache/ApplicationCacheHost.h"
+#include "core/origin_trials/OriginTrials.h"
 #include "core/page/ChromeClient.h"
 #include "core/page/CreateWindow.h"
 #include "core/page/FrameTree.h"
@@ -483,6 +484,8 @@ void FrameLoader::didBeginDocument(bool dispatch)
             if (!headerContentLanguage.isEmpty())
                 m_frame->document()->setContentLanguage(AtomicString(headerContentLanguage));
         }
+
+        OriginTrials::setTrialTokensFromHeader(m_frame->document(), m_documentLoader->response().httpHeaderField(HTTPNames::Origin_Trial));
     }
 
     if (m_provisionalItem && isBackForwardLoadType(m_loadType))