Bring up idletimer unittest on Mac port.

base/idle_timer.cc

Index: base/idle_timer.cc
===================================================================
--- base/idle_timer.cc	(revision 3254)
+++ base/idle_timer.cc	(working copy)
@@ -4,15 +4,48 @@
 
 #include "base/idle_timer.h"
 
+#if defined(OS_MACOSX)
+#include <ApplicationServices/ApplicationServices.h>
+#endif
+
 #include "base/message_loop.h"
 #include "base/time.h"
 
 namespace base {
 
+#if defined(OS_WIN)
+bool OSIdleTimeSource(int32 *milliseconds_interval_since_last_event) {
+  LASTINPUTINFO lastInputInfo;
+  lastInputInfo.cbSize = sizeof(lastInputInfo);
+  if (GetLastInputInfo(&lastInputInfo) == 0) {
+    return false;
+  }
+  int32 last_input_time = lastInputInfo.dwTime;
+  
+  // Note: On Windows GetLastInputInfo returns a 32bit value which rolls over 
+  // ~49days.
+  int32 current_time = GetTickCount();
+  int32 delta = current_time - last_input_time;
+  // delta will go negative if we've been idle for 2GB of ticks.
+  if (delta < 0)
+    delta = -delta;    
+  *milliseconds_interval_since_last_event = delta;
+  return true;
+}
+#elif defined(OS_MACOSX)
+bool OSIdleTimeSource(int32 *milliseconds_interval_since_last_event) {
+  *milliseconds_interval_since_last_event = 
+      CGEventSourceSecondsSinceLastEventType(
+          kCGEventSourceStateCombinedSessionState, 
+          kCGAnyInputEventType) * 1000.0;
+  return true;
+}
+#endif
+
 IdleTimer::IdleTimer(TimeDelta idle_time, bool repeat)
     : idle_interval_(idle_time),
       repeat_(repeat),
-      get_last_input_info_fn_(GetLastInputInfo) {
+      idle_time_source_(OSIdleTimeSource) {
   DCHECK_EQ(MessageLoop::TYPE_UI, MessageLoop::current()->type()) <<
       "Requires a thread that processes Windows UI events";
 }
@@ -48,17 +81,8 @@
 }
 
 TimeDelta IdleTimer::CurrentIdleTime() {
-  // TODO(mbelshe): This is windows-specific code.
-  LASTINPUTINFO info;
-  info.cbSize = sizeof(info);
-  if (get_last_input_info_fn_(&info)) {
-    // Note: GetLastInputInfo returns a 32bit value which rolls over ~49days.
-    int32 last_input_time = info.dwTime;
-    int32 current_time = GetTickCount();
-    int32 interval = current_time - last_input_time;
-    // Interval will go negative if we've been idle for 2GB of ticks.
-    if (interval < 0)
-      interval = -interval;
+  int32 interval = 0;
+  if (idle_time_source_(&interval)) {
     return TimeDelta::FromMilliseconds(interval);
   }
   NOTREACHED();