Implement frame attribution (FrameBlamer)

third_party/WebKit/public/platform/Platform.h

Index: third_party/WebKit/public/platform/Platform.h
diff --git a/third_party/WebKit/public/platform/Platform.h b/third_party/WebKit/public/platform/Platform.h
index 8f39386ce39e01b52858cebe2df32a72de6a8913..f693a6db4f6d3ca5d7213c4127d768af52fc49f5 100644
--- a/third_party/WebKit/public/platform/Platform.h
+++ b/third_party/WebKit/public/platform/Platform.h
@@ -35,6 +35,7 @@
 #include <windows.h>
 #endif
 
+#include "BlameContext.h"
 #include "UserMetricsAction.h"
 #include "WebAudioDevice.h"
 #include "WebCommon.h"
@@ -358,6 +359,9 @@ public:
     // embedder.
     virtual WebThread* currentThread() { return nullptr; }
 
+    // Returns a blame context for attributing work to the thread-global scope.
+    virtual BlameContext* threadBlameContext() { return nullptr; }

[esprehn, 2016/03/31 00:47:04]

can this get a better name? Platform is used by many threads.

[Sami, 2016/03/31 10:29:49]

I've changed it to "topLevelBlameContext" with a more informative comment.

+
     // Resources -----------------------------------------------------------
 
     // Returns a blob of data corresponding to the named resource.