QUIC - track disk cache API calls and failure reasons in separate

net/http/disk_cache_based_quic_server_info.h

Index: net/http/disk_cache_based_quic_server_info.h
diff --git a/net/http/disk_cache_based_quic_server_info.h b/net/http/disk_cache_based_quic_server_info.h
index 97fe95e10c79b08da35b84b9fcf8da9c6f75612f..7c9467e3424e00238d7c015fd0421a8f94871236 100644
--- a/net/http/disk_cache_based_quic_server_info.h
+++ b/net/http/disk_cache_based_quic_server_info.h
@@ -41,6 +41,7 @@ class NET_EXPORT_PRIVATE DiskCacheBasedQuicServerInfo
 
  private:
   struct CacheOperationDataShim;
+
   enum State {
     GET_BACKEND,
     GET_BACKEND_COMPLETE,
@@ -57,6 +58,34 @@ class NET_EXPORT_PRIVATE DiskCacheBasedQuicServerInfo
     NONE,
   };
 
+  // Enum to track number of times data read/parse/write API calls of
+  // QuicServerInfo to and from disk cache is called.
+  enum QuicServerInfoAPICall {
+    QUIC_SERVER_INFO_START = 0,
+    QUIC_SERVER_INFO_WAIT_FOR_DATA_READY = 1,
+    QUIC_SERVER_INFO_PARSE = 2,
+    QUIC_SERVER_INFO_WAIT_FOR_DATA_READY_CANCEL = 3,
+    QUIC_SERVER_INFO_READY_TO_PERSIST = 4,
+    QUIC_SERVER_INFO_PERSIST = 5,
+    QUIC_SERVER_INFO_NUM_OF_API_CALLS = 6,
+  };
+
+  // Enum to track failure reasons to read/load/write of QuicServerInfo to
+  // and from disk cache.
+  enum FailureReason {
+    WAIT_FOR_DATA_READY_INVALID_ARGUMENT_FAILURE = 0,
+    GET_BACKEND_FAILURE = 1,
+    OPEN_FAILURE = 2,
+    CREATE_OR_OPEN_FAILURE = 3,
+    PARSE_NO_DATA_FAILURE = 4,
+    PARSE_FAILURE = 5,
+    READ_FAILURE = 6,
+    READY_TO_PERSIST_FAILURE = 7,
+    PERSIST_NO_BACKEND_FAILURE = 8,
+    WRITE_FAILURE = 9,
+    NUM_OF_FAILURES = 10,
+  };
+
   ~DiskCacheBasedQuicServerInfo() override;
 
   std::string key() const;
@@ -86,6 +115,14 @@ class NET_EXPORT_PRIVATE DiskCacheBasedQuicServerInfo
   // DoSetDone is the terminal state of the write operation.
   int DoSetDone();
 
+  // Tracks in a histogram the number of times data read/parse/write API calls
+  // of QuicServerInfo to and from disk cache is called.
+  void RecordQuicServerInfoStatus(QuicServerInfoAPICall call);
+
+  // Tracks in a histogram the failure reasons to read/load/write of
+  // QuicServerInfo to and from disk cache.
+  void RecordQuicServerInfoFailure(FailureReason failure);
+
   CacheOperationDataShim* data_shim_;  // Owned by |io_callback_|.
   CompletionCallback io_callback_;
   State state_;