Revert of tracing v2: Introduce TraceBufferWriter

components/tracing/core/scattered_stream_writer.h

Index: components/tracing/core/scattered_stream_writer.h
diff --git a/components/tracing/core/scattered_stream_writer.h b/components/tracing/core/scattered_stream_writer.h
index 53fcd881dcd098972a6f572d57129fe3db4e17fe..8fbf84cbeb2c7330bbc6fb821c8fc130cf01dca7 100644
--- a/components/tracing/core/scattered_stream_writer.h
+++ b/components/tracing/core/scattered_stream_writer.h
@@ -38,9 +38,8 @@
 // ContiguousMemoryRange and defers the chunk-chaining logic to the Delegate.
 class TRACING_EXPORT ScatteredStreamWriter {
  public:
-  class TRACING_EXPORT Delegate {
+  class Delegate {
    public:
-    virtual ~Delegate();
     virtual ContiguousMemoryRange GetNewBuffer() = 0;
   };