logd: always report the UID of a log message

logd currently only reports the UID of a log message for 'privileged'
readers (those with a uid or gid of root, system, or log).  However,
UIDs are not particularly sensitive.  Much more importantly,
non-privileged readers can only see less messages from their own UID,
so this restriction is essentially a no-op, as those readers will
already know their own uid.

Test: liblog and logd unit tests
Change-Id: I9da7d15eb840ba3200128391e70d618eec79f988
diff --git a/logd/LogBufferElement.cpp b/logd/LogBufferElement.cpp
index 82c4fb9..5c43e18 100644
--- a/logd/LogBufferElement.cpp
+++ b/logd/LogBufferElement.cpp
@@ -244,14 +244,10 @@
     return retval;
 }
 
-log_time LogBufferElement::flushTo(SocketClient* reader, LogBuffer* parent,
-                                   bool privileged, bool lastSame) {
-    struct logger_entry_v4 entry;
+log_time LogBufferElement::flushTo(SocketClient* reader, LogBuffer* parent, bool lastSame) {
+    struct logger_entry_v4 entry = {};
 
-    memset(&entry, 0, sizeof(struct logger_entry_v4));
-
-    entry.hdr_size = privileged ? sizeof(struct logger_entry_v4)
-                                : sizeof(struct logger_entry_v3);
+    entry.hdr_size = sizeof(struct logger_entry_v4);
     entry.lid = mLogId;
     entry.pid = mPid;
     entry.tid = mTid;