Remove unused code and comments for socket annotations.

Not required codes and comments related to sockets annotations are
removed from several classes. The changes include:
 - Default network traffic annotation values are removed and test tags
   are added instead if required.
 - Code to store annotations in sockets is removed.
 - Comments regarding annotations storage is removed.

Bug: 656607
Change-Id: I716dd482a6e868ba3b634437c434950db6073332
Reviewed-on: https://chromium-review.googlesource.com/823965
Commit-Queue: Ramin Halavati <[email protected]>
Reviewed-by: Jochen Eisinger <[email protected]>
Cr-Commit-Position: refs/heads/master@{#523778}
diff --git a/net/socket/fuzzed_socket_factory.cc b/net/socket/fuzzed_socket_factory.cc
index fcdad66..ca158aea 100644
--- a/net/socket/fuzzed_socket_factory.cc
+++ b/net/socket/fuzzed_socket_factory.cc
@@ -38,12 +38,10 @@
     return ERR_UNEXPECTED;
   }
 
-  // TODO(crbug.com/656607): Remove default value.
   int Write(IOBuffer* buf,
             int buf_len,
             const CompletionCallback& callback,
-            const NetworkTrafficAnnotationTag& traffic_annotation =
-                NO_TRAFFIC_ANNOTATION_BUG_656607) override {
+            const NetworkTrafficAnnotationTag& traffic_annotation) override {
     NOTREACHED();
     return ERR_UNEXPECTED;
   }