QTimerInfoList: improve class encapsulation

Replace the only usage of updateCurrentTime() outside of the class by a
getter that checks if there are pending timers. And make
updateCurrentTime() private.

Change-Id: I148639b01abd75990cfc7b25bb1f466e45ab0c71
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/kernel/qeventdispatcher_glib.cpp

@@ -110,10 +110,7 @@ static gboolean timerSourceCheckHelper(GTimerSource *src)
         || (src->processEventsFlags & QEventLoop::X11ExcludeTimers))
         return false;
 
-    if (src->timerList.updateCurrentTime() < src->timerList.constFirst()->timeout)
-        return false;
-
-    return true;
+    return !src->timerList.hasPendingTimers();
 }
 
 static gboolean timerSourcePrepare(GSource *source, gint *timeout)

src/corelib/kernel/qtimerinfo_unix.cpp

@@ -33,6 +33,19 @@ steady_clock::time_point QTimerInfoList::updateCurrentTime()
     return currentTime;
 }
 
+/*! \internal
+    Updates the currentTime member to the current time, and returns \c true if
+    the first timer's timeout is in the future (after currentTime).
+
+    The list is sorted by timeout, thus it's enough to check the first timer only.
+*/
+bool QTimerInfoList::hasPendingTimers()
+{
+    if (isEmpty())
+        return false;
+    return updateCurrentTime() < constFirst()->timeout;
+}
+
 /*
   insert timer info into list
 */

src/corelib/kernel/qtimerinfo_unix_p.h

@@ -43,7 +43,6 @@ public:
     QTimerInfoList();
 
     std::chrono::steady_clock::time_point currentTime;
-    std::chrono::steady_clock::time_point updateCurrentTime();
 
     bool timerWait(timespec &);
     void timerInsert(QTimerInfo *);
@@ -59,12 +58,16 @@ public:
     QList<QAbstractEventDispatcher::TimerInfo> registeredTimers(QObject *object) const;
 
     int activateTimers();
+    bool hasPendingTimers();
 
     QList::const_iterator findTimerById(int timerId) const
     {
         auto matchesId = [timerId](const QTimerInfo *t) { return t->id == timerId; };
         return std::find_if(cbegin(), cend(), matchesId);
     }
+
+private:
+    std::chrono::steady_clock::time_point updateCurrentTime();
 };
 
 QT_END_NAMESPACE