Merge #10129: scheduler: fix sub-second precision with boost < 1.50

e025246 scheduler: fix sub-second precision with boost < 1.50 (Cory Fields)

Tree-SHA512: b9d4875406c1a2bf3cb6412d7511c24d871bfba6a2ea5ccfbbf7392f2f8850027b001b776da422fea592878da21d897b1aa56d92bc2239869055dce79fd442ac

src/scheduler.cpp

@@ -23,7 +23,9 @@ CScheduler::~CScheduler()
 #if BOOST_VERSION < 105000
 static boost::system_time toPosixTime(const boost::chrono::system_clock::time_point& t)
 {
-    return boost::posix_time::from_time_t(boost::chrono::system_clock::to_time_t(t));
+    // Creating the posix_time using from_time_t loses sub-second precision. So rather than exporting the time_point to time_t,
+    // start with a posix_time at the epoch (0) and add the milliseconds that have passed since then.
+    return boost::posix_time::from_time_t(0) + boost::posix_time::milliseconds(boost::chrono::duration_cast<boost::chrono::milliseconds>(t.time_since_epoch()).count());
 }
 #endif