CompressedStringDataSink for trace_controller.

content/public/browser/tracing_controller.h

Index: content/public/browser/tracing_controller.h
diff --git a/content/public/browser/tracing_controller.h b/content/public/browser/tracing_controller.h
index 0cbed7018d64edb5e6a0c9e3b8f40cf5179fc723..37ac2f75551b9cab659d1955b3495d6b9fe3ce02 100644
--- a/content/public/browser/tracing_controller.h
+++ b/content/public/browser/tracing_controller.h
@@ -45,11 +45,29 @@ class TracingController {
     virtual ~TraceDataSink() {}
   };
 
+  // An implementation of this interface is passed when constructing a
+  // TraceDataSink, and receives chunks of the final trace data as it's being
+  // constructed.
+  // Methods may be called from any thread.
+  class CONTENT_EXPORT TraceDataEndpoint
+      : public base::RefCountedThreadSafe<TraceDataEndpoint> {
+   public:
+    virtual void ReceiveTraceChunk(const std::string& chunk) {}
+    virtual void ReceiveTraceFinalContents(const std::string& contents) {}
+
+   protected:
+    friend class base::RefCountedThreadSafe<TraceDataEndpoint>;
+    virtual ~TraceDataEndpoint() {}
+  };
+
   // Create a trace sink that may be supplied to DisableRecording or
   // CaptureMonitoringSnapshot to capture the trace data as a string.
   CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateStringSink(
       const base::Callback<void(base::RefCountedString*)>& callback);
 
+  CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateCompressedStringSink(
+      scoped_refptr<TraceDataEndpoint> endpoint);
+
   // Create a trace sink that may be supplied to DisableRecording or
   // CaptureMonitoringSnapshot to dump the trace data to a file.
   CONTENT_EXPORT static scoped_refptr<TraceDataSink> CreateFileSink(