logd: remove LogBufferElement dependency of LogReaderThread

In the future, not all log buffers will be implemented in terms of
LogBufferElement.

Test: build
Change-Id: I5cf0d01414857b1bfa08c92a4f8035b43ef2aad7
diff --git a/logd/SimpleLogBuffer.h b/logd/SimpleLogBuffer.h
index cd08acf..72d26b0 100644
--- a/logd/SimpleLogBuffer.h
+++ b/logd/SimpleLogBuffer.h
@@ -35,9 +35,10 @@
 
     int Log(log_id_t log_id, log_time realtime, uid_t uid, pid_t pid, pid_t tid, const char* msg,
             uint16_t len) override;
-    uint64_t FlushTo(
-            LogWriter* writer, uint64_t start, pid_t* lastTid,
-            const std::function<FilterResult(const LogBufferElement* element)>& filter) override;
+    uint64_t FlushTo(LogWriter* writer, uint64_t start, pid_t* lastTid,
+                     const std::function<FilterResult(log_id_t log_id, pid_t pid, uint64_t sequence,
+                                                      log_time realtime, uint16_t dropped_count)>&
+                             filter) override;
 
     bool Clear(log_id_t id, uid_t uid) override;
     unsigned long GetSize(log_id_t id) override;